Answer:
Rafter also called roof joist.
Explanation:
In roof framing, a rafter serves as the structural member that supports the building's roof. It is part of a rigid structure that is essential for the stability of the roof. Historically, other elements like engaged columns and buttresses were also used to support and stabilize the building structure.
Explanation:With roof framing, a rafter is a structural member that supports the roof of a building. A rafter is part of a rigid structure formed of relatively slender pieces, which are typically joined together to support the roof. This is critical in roofing as it helps distribute the weight of the roof and ensures the stability of the building.
The history of roof construction shows that the types of construction varied based on the available natural materials. Load-bearing walls played a vital role in supporting the roofs and had to be constructed strong enough not only to support themselves but also the roof. If the roof span was too large, the walls could be pushed out and collapse.
Trenton collects a sample of moist air. One of these factors is unrelated to the amount water vapor in his sample. Which factor is it? A. Pressure B. Temperature C. Vapor density D. Volume E. Wind speed
Wind speed is unrelated to the amount of water vapour in the sample of moist air.
Answer: Option E
Explanation:
As the sample of moist air is combination of water vapour mixed with air molecules, there will be no generation of wind in the moist air. But there will be change in the pressure and temperature when water vapours or moisture mixes with air molecules.
As water is having high density compared to air molecules, the pressure will be changed in moist air. So, the amount of water vapour in the moist air sample can measure by relative difference in pressure, temperature, vapour density and volume with air molecules in general.
Answer:
Answer E
Explanation:
The longest wavelength of light with enough energy to break the Cl-Cl bond in Cl2(g) is 495 nm.
1) calculate the frequency in s-1 of the light2) calculate the energy in J of a photon of the light3) calculate the minimun energy in KJ mol-1 of the cl-cl bond
Explanation:
The longest wavelength of light with enough energy to break the Cl-Cl bond = 495 nm = [tex]495\times 10^{-9} m[/tex]
1) The frequency of the light:
[tex]\lambda =495\times 10^{-9} m[/tex]
[tex]\nu=\frac{c}{\lambda }[/tex]
c = speed of light= [tex]3\times 10^8 m/s[/tex]
[tex]\nu=\frac{3\times 10^8 m/s}{495\times 10^{-9} m}[/tex]
[tex]=6.0606\times 10^{14) s^{-1}[/tex]
The frequency of the light is [tex]6.0606\times 10^{14) s^{-1}[/tex].
2)The energy of a photon of the light:
The energy of the photon is given by : E
[tex]E=h\nu [/tex]
h = Planck's constant = [tex]6.626\times 10^{-34} J/s[/tex]
[tex]E=6.626\times 10^{-34} J/s\times 6.0606\times 10^{14) s^{-1}[/tex]
[tex]=4.016\times 10^{-19} J[/tex]
The energy of a photon of the light is [tex]4.016\times 10^{-19} J[/tex].
3) The minimum energy of the Cl-Cl bond :
To break single bond of Cl-Cl bond we need energy E= [tex]4.016\times 10^{-19} J[/tex]
1 mole = [tex]N_A=6.022\times 10^{23} mol^{-1} [/tex]
So, in order to break 1 mole of Cl-Cl bond we will need:
[tex]E\times N_A=4.016\times 10^{-19} J\times 6.022\times 10^{23} mol^{-1} [/tex]
[tex]=241,828.92 J/mol=241,828.92\times 0.001 kJ/mol=241.83 kJ/mol[/tex]
The minimum energy of the Cl-Cl bond is 241.83 kJ/mol.
The frequency of the light radiation has been 6.0606 × [tex]\rm 10^1^4[/tex] /sec. The energy of the light photon has been 4.016 × [tex]\rm 10^-^1^9[/tex] J. The minimum energy in the Cl-Cl bond has been 241.8292 kJ/mol.
(1) The frequency can be defined as the number of times the wave has been repeated, while the wavelength has been defined as the distance of one wave.
The frequency of the wave in the air can be given as:
Frequency = [tex]\rm \dfrac{speed}{wavelength}[/tex]
Frequency of 495 nm wavelength has been :
Frequency = [tex]\rm \dfrac{3\;\times\;10^8\;m/sec}{495\;\times\;10^-^9\;m}[/tex]
Frequency = 6.0606 × [tex]\rm 10^1^4[/tex] /sec
The frequency of the light radiation has been 6.0606 × [tex]\rm 10^1^4[/tex] /sec.
(2) The energy of the light photon has been given by:
Energy = Plank's constant × Frequency
Energy = 6.626 × [tex]\rm 10^-^3^4[/tex] J/s × 6.0606 × [tex]\rm 10^1^4[/tex] /sec
The energy of the photon = 4.016 × [tex]\rm 10^-^1^9[/tex] J.
The energy of the light photon has been 4.016 × [tex]\rm 10^-^1^9[/tex] J.
(3) The minimum energy of Cl-Cl bond has been given by:
The energy for 1 photon = 4.016 × [tex]\rm 10^-^1^9[/tex] J.
The energy for 1 mole of Cl-Cl has been the minimum energy for breaking Cl-Cl bond.
1 mole = 6.023 × [tex]\rm 10^2^3[/tex] atoms
Energy for Cl-Cl bond has been = 4.016 × [tex]\rm 10^-^1^9[/tex] J × 6.023 × [tex]\rm 10^2^3[/tex] atoms
Energy for Cl-Cl bond has been = 241,828.92 J/mol
Energy for Cl-Cl bond has been = 241.8292 kJ/mol.
The minimum energy in the Cl-Cl bond has been 241.8292 kJ/mol.
For more information about frequency, refer to the link:
https://brainly.com/question/4393505
What is the correct numerical setup for calculating the final volume of the helium gas sample?
Answer:
This question is incomplete. But the completed question is below
A sample of helium gas is in a closed system with a movable piston. The volume of the gas sample is changed when both the temperature and the pressure of the sample are increased. Where the initial temperature of the gas is 200K, initial pressure is 2.0 atm, initial volume is 500 mL, the final temperature is 300K and the final pressure of the gas sample is 7.0 atm.
What is the correct numerical setup for calculating the final volume of the helium gas sample?
P₁V₁/T₁ = P₂V₂/T₂ will be used in calculating the final volume.
And the final volume is 214.29 mL
Explanation:
The general gas equation will be used to calculate the final volume. The general gas equation is
P₁V₁/T₁ = P₂V₂/T₂
From the question
P₁ = 2.0 atm
T₁ = 200K
V₁ = 500 mL
P₂ = 7.0 atm
T₂ = 300K
V₂ = unknown
Hence, we have
2 × 500/200 = 7 × V₂/300
V₂ = [tex]\frac{2 * 500 * 300}{200 * 7}[/tex]
V₂ = 214.29 mL
The final volume of He gas sample has been 214.285 mL.
Helium has been assumed to be an ideal gas. The final volume of the gas with an increase in pressure has been given by:
[tex]\dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}[/tex]
Where, the initial pressure of gas, [tex]P_1=2\;\text{atm}[/tex]
The final pressure of gas, [tex]P_2=7\;\text{atm}[/tex]
The initial volume of gas, [tex]V_1=500\;\text{ml}[/tex]
The initial temperature of gas, [tex]T_1=200\;\text K[/tex]
The final temperature of gas, [tex]T_2=300\;\text K[/tex]
Substituting the values for the final temperature of He, [tex]V_2[/tex]:
[tex]\dfrac{2\;\times\;500}{200}=\dfrac{7\;\times\;V_2}{300}\\\\\dfrac{2\;\times\;500}{200}\;\times\;\dfrac{300}{7} = V_2\\\\V_2=214.285\;\rm ml[/tex]
The final volume of He gas has been 214.285 mL.
For more information about the volume of gas, refer to the link:
https://brainly.com/question/1323061
A 15.85g piece of iron absorbs 1086.75 joules of heat energy and its temperature changes from 25 degrees Celsius to 175 degrees celcius. Calculate the specific heat capacity of iron.
Answer:
Explanation:
Specific heat capacity of iron is the amount of heat required to raise 1g of iron by 1 degree Celsius.
The formula is Q=mc∆T
Where Q is energy in joules.
M is mass in gram.
C is specific heat capacity in J/g°C.
∆T is change in temperature in degree Celsius
Q=1086.75joules
M=15.85g
C=?
∆T = final T-initial T(175-25)=150°c.
Q=Mc∆T
1086.75= 15.85×C×150
1086.85=2377.5c
C=1086.85÷2377.5
C=0.46J/g°C.
Lithium ion salts were originally found in Seven-Up® drinks. How many electrons does Li atom lose to become an ion?
Answer: One (1) electron
Explanation:
Lithium is a group 1 element with an atomic number of 3. Thus, it has just 3 electrons and its electronic configuration is 1s2, 2s1
To become lithium ion salts, it gives off its lone electron thereby becoming Li+ with configuration of 1s2 with just 2 electrons left.
So, Li atom loses only ONE ELECTRON to become an ion
Click the "draw structure" button to launch the drawing utility. under certain reaction conditions, 2,3−dibromobutane reacts with two equivalents of base to give three products, each of which contains two new π bonds. product a has two sp hybridized carbon atoms, product b has one sp hybridized carbon atom, and product c has none. what is the structure of b?
Answer:
Explanation:
According to this. Let's analize the possible products a, b and c.
First, the problem states that we have 2 eq. of base, For this case, let's assume it's KOH. Now, As we are doing a reaction with base, means that this reaction can only take places under conditions of SN2 and E2, a fast reaction that is taking place in only 1 step.
With this in mind, let's analyze product a. This states that it has two sp hybridized carbon, in other words, a triple bond between two carbons. So the product is with no doubt, an alkyne.
Product b has only one sp hybridized carbon, which means that this carbon should cannot be an alkyne because we need two carbon atoms. The only way to have one atom of C sp hybridized, is with two double bonds, so product b would have to a alkene with two double bonds.
Product c do not have sp hybridized carbon, therefore, it only has two double bonds in two different Carbon atoms, so it's another alkene with two double bonds, but in two different atoms of carbon.
Picture attached show the product a, b and c. Hope this can help
In a reaction involving 2,3-dibromobutane and a base, three products with distinct arrangements of π bonds and sp hybridized carbons are formed. Given that Product B has one sp hybridized carbon, it is likely to be 2-butyne.
Explanation:In the reaction of 2,3-dibromobutane with two equivalents of a base, the base will act as a nucleophile and attack the carbon atoms bound to the bromine atoms. This will then form three products, each with two new π bonds. Given that Product B has one sp hybridized carbon atom, it is likely that this product is 2-butyne. 2-butyne has one in which both are on the same side producing a cis- configuration, and one in which they are on opposite sides producing a trans- configuration.
Learn more about Chemical Reaction here:https://brainly.com/question/34137415
#SPJ12
Predict the sign of ΔSsys for each process. Which are positive? A. A pond freezes in winter. B. Atmospheric CO2 dissolves in the ocean. C. An apple tree bears fruit. D. None of them are positive. Which are negative? A. A pond freezes in winter. B. Atmospheric CO2 dissolves in the ocean. C. An apple tree bears fruit. D. None of them are negative.
Answer:
Which are positive? D.
Which are negative? A. B. C.
Explanation:
Generally, entropy can be defined as the degree of randomness of a system. The entropy of any system increases with an increase in the number of moles of the system. Entropy also increases when there is a change of state from solid to liquid or liquid to gas. Therefore for the systems in the given question:
A pond freezes in winter
The degree of disorderliness decrease because there is a change of state from liquid to solid. Thus, ΔSsys is negative.
Atmospheric CO2 dissolves in the ocean
There is also decrease in randomness, thus, ΔSsys is negative.
An apple tree bears fruit
There is also decrease in randomness, thus, ΔSsys is negative.
A pond freezes in winter, atmospheric CO2 dissolves in the ocean, and an apple tree bears fruit are negative changes in Delta S.
What is Delta S?Delta S is a measurement used in thermodynamics to calculate the modifications in the level of entropy.
The term entropy makes reference to the degree of randomness (disorder) of a thermodynamic system. A negative delta S involves a decrease in entropy (disorder) regarding a particular system.In conclusion, a pond freezes in winter, atmospheric CO2 dissolves in the ocean, and an apple tree bears fruit are negative changes in Delta S.
Learn more in:
https://brainly.com/question/6364271
Phospholipids, molecules found within a cell membrane, have hydrophobic tails and hydrophilic heads. These regions act in the same manner that hydrophobic and hydrophilic amino acids act. When phospholipids are found as a sphere in a glass of water, which of the following would you expect:
Answer:
The correct answer is "The hydrophilic heads will point toward the water, and the hydrophobic tails will point away from the water".
Explanation:
The missing options of this question are:
a. The hydrophobic tails will point toward the water, and the hydrophilic heads will point away from the water.
b. The hydrophilic heads will point toward the water, and the hydrophobic tails will point away from the water.
c. Hydrophilic heads and hydrophobic tails will both point toward the water.
d. The hydrophobic tails and hydrophilic heads will be arranged randomly.
The correct answer is option b. Phospholipids are amphiphilic molecules that have hydrophilic heads and hydrophobic tails. This characteristic makes them the main component of cell's membrane where the hydrophilic tails point outside and inside the cell, and the hydrophobic tails point within the membrane. If phospholipids are found as a sphere in a glass of water, the hydrophilic heads will point toward the water, and the hydrophobic tails will point away from the water. This is the most stable structure, therefore, this will be the arrangement of the phospholipids.
When reacting with an atom of fluorine, an atom of lithium will lose an electron and become a lithium
a. crystal
b. molecule
c. compound
d. ion
When reacting with an atom of fluorine, an atom of lithium will lose an electron and become a lithium ion.
Answer: Option D
Explanation:
Most of the chemical reactions or diffusion occurs by transfer of electrons among the elements combining to form a material. So depending on the type of bonding existed in any molecule, the strength of the bonding and its directionality can be measured.
Basically two or mole elements combine to form a compound and in this process, one of the element need to give some amount of electron to the other elements. And this transfer of electrons can be known from their oxidation state. As the element is giving or taking an electron from/to other element, that corresponding donating element and receiving element will be termed as ions from atoms.
So, the element which has the tendency to give electron easily will form positive ions and similarly, the element which is known for attracting electrons towards itself is termed as negative ions. So in this case, on reaction of fluorine with lithium, the lithium will lose an electron and become a lithium ion.
Choose the following statements that show evidence for a chemical reaction.
1. Dropping sodium metal into water produces fizzing
2. Dissolving a white powder in solution gives white light
3. Mixing two aqueous solutions produces a precipitate
4. Mixing two 10.0 mL solutions gives a volume of 19.5 mL
Explanation:
A chemical reaction is defined as the reaction in which bonds between the reactants either break or form which leads to the formation of a new substance.
For example, [tex]2Li + Cl_{2} \rightarrow 2LiCl[/tex]
So, when we drop a sodium metal into water then it produces a frizzing sound which shows the metal is reacting with water.
We know that when two aqueous solutions chemically react with each other then it may lead to the formation of an insoluble substance which is known as precipitate.
This means that formation of a precipitate is also a chemical reaction.
Thus, we can conclude that following are the statements which show evidence for a chemical reaction.
Dropping sodium metal into water produces fizzing.Mixing two aqueous solutions produces a precipitate.Assuming the metals lose all their valence electrons and the nonmetals gain electrons to complete the s-p subshells, which listing below shows the correct information for the element?Elements Electron Structure of Atom Electron Structure of Ion Net Ion Charge:1. sodium 1s22s22p63s1 1s22s22p6 -12. fluorine 1s22s22p4 1s22s22p6 -13. aluminum 1s22s22p63s23p1 1s22s22p6 +3a. The listing for sodium is correct.b. The listing for fluorine is correct.c. The listing for aluminum is correct.d. None of these
Answer: Option (c) is the correct answer.
Explanation:
Atomic number of sodium is 11 and its electronic configuration is [tex]1s^{2}2s^{2}2p^{6}3s^{1}[/tex]. When sodium loses one electron then it will attain +1 charge and its electronic configuration will be as follows.
[tex]Na^{+}[/tex] : [tex]1s^{2}2s^{2}2p^{6}[/tex]
Atomic number of fluorine is 9 and its electronic configuration is [tex]1s^{2}2s^{2}2p^{5}[/tex]. When fluorine gains an electron then it acquires -1 charge and its electronic configuration is as follows.
[tex]F^{-}[/tex] : [tex]1s^{2}2s^{2}2p^{6}[/tex]
Atomic number of aluminium is 13 and its electronic configuration is [tex]1s^{2}2s^{2}2p^{6}3s^{2}3p^{1}[/tex]. When aluminium loses its valence electrons then it acquires +3 charge and its electronic configuration is as follows.
[tex]Al^{3+}[/tex] : [tex]1s^{2}2s^{2}2p^{6}[/tex]
Thus, we can conclude that the listing for aluminum is correct.
Final answer:
The correct listing according to the electron structures of atoms and ions is for aluminum, which has an atomic structure of 1s²2s²2p¶3s²3p¹ and as an ion it has a structure of 1s²2s²2p¶ with a net charge of +3.
Explanation:
The student has asked to identify the correct listing of electron structure of an atom and the resulting ion, as well as the net ion charge for sodium, fluorine, and aluminum. In the case of sodium (Na), the atom has an electronic structure of 1s²2s²2p¶3s¹ and the sodium ion will have a structure of 1s²2s²2p¶ with a net charge of +1 after losing one valence electron. For fluorine, the atom has a structure of 1s²2s²2p¶4 and as a fluoride ion, it gains one electron to complete its valence shell, resulting in 1s²2s²2p¶ and a -1 charge. Lastly, aluminum (Al) has an electronic structure of 1s²2s²2p¶3s²3p¹. When it forms an ion, it loses three electrons becoming 1s²2s²2p¶ with a net charge of +3. Based on this information, choice c, the listing for aluminum is correct.
A Beer's law plot for Cu2+ was experimentally obtained. The slope of the Beer's law plot was 310 L/mol (with a y-intercept = 0.001). A Cu2+ solution of unknown concentration had an absorbance of 0.55. What is the molar concentration of Cu2+ in the unknown solution?
Answer:
[tex]1.7742\times 10^{-3} mol/L[/tex] is the molar concentration of Cu(II) ions in the unknown solution.
Explanation:
Using Beer-Lambert's law :
Formula used :
[tex]A=\epsilon \times C\times l[/tex]
where,
A = absorbance of solution
C = concentration of solution
l = length of the cell =
[tex]\epsilon[/tex] = molar absorptivity of solution
A Beer's law plot is between absorbance and concentration.
[tex]\frac{A}{c}=Slope(m)=\epsilon\times l[/tex]
We have:
A = 0.55
The slope of the Beer's law plot = m = 310 L/mol
So, the concentration of the solution is:
[tex]c=\frac{A}{m}=\frac{0.55}{310 L/mol}=1.7742\times 10^{-3} mol/L[/tex]
[tex]1.7742\times 10^{-3} mol/L[/tex] is the molar concentration of Cu(II) ions in the unknown solution.
Using Beer's law and the given slope and absorbance values, the molar concentration of Cu2+ in the solution is approximately 1.77 * [tex]10^{-3[/tex] M.
Explanation:Beer's law, also known as the Beer-Lambert law, establishes a linear relationship between the absorbance of a species in a solution and its concentration. The equation for Beer's law is A = εlc, where A is absorbance, ε is the molar absorptivity (given by the slope in this case), l is the path length (assumed to be 1 cm here), and c is the concentration. In your case, the slope is 310 L/mol, and you have measured an absorbance of 0.55.
To find the concentration of Cu2+ in the solution, we rearrange the Beer's law equation to c = A / εl. Substituting in your values, we get c = 0.55 / (310 L/mol * 1 cm), which simplifies to c = 0.00177 mol/L or 1.77 * [tex]10^{-3[/tex] M. So the molar concentration of Cu2+ in the unknown solution is approximately 1.77 * [tex]10^{-3[/tex] M.
Learn more about Molar Concentration here:https://brainly.com/question/15532279
#SPJ11
The emission spectrum of an element:
A. may be identical to the emission spectrum of another element.
B. is identical to its absorption spectrum.
C. may be identical to the absorption spectrum of another element.
D. is different from any other element's absorption spectrum.
B
The emission spectrum of an element is identical to its absorption spectrum.
Explanation:
This is because a quantum leap of an electron of an atom from one lower energy level to a higher one results in the absorption of a specific wavelength of electromagnetic radiation. When the electron leaps back to the lower energy level, it releases the same wavelength of electromagnetic radiation. This is according to Bohr's theory. Every atom has a signature absorption and emission spectra that are used to identify it.
Learn More:
For more on Bohr theory of the atom check out;
https://brainly.com/question/5839092
https://brainly.com/question/12479859
https://brainly.com/question/1528920
#LearnWithBrainly
The smallest units of matter that normally CANNOT be broken down are atoms. molecules. cells. phospholipids.
Answer: atoms
Explanation:
All matter is made up of smaller indivisible particles called atoms. These atoms are the smallest units of matter ACCORDING to the Dalton's Atomic theory.
Molecules are combined atoms, while cells and phospholipids are complex combination of atoms.
Therefore, atoms is the answer
Which of the following is not a correct chemical equation for a double displacement reaction?
A. 2RbNO3 + BeF2 yields Be(NO3)2 + 2RbF
B.CaCl + LiCO3 yields CaCO3 + LiCl
C. Na3PO4 + 3KOH yields 3NaOH + K3PO4
D. 2MgI2 + Mn(SO3)2 yields 2MgSO3 + MnI4
Answer:
B. CaCl + LiCO3 yields CaCO3 + LiCl is not correct
It should be CaCl2 + Li2CO3 → 2LiCl + CaCO3
Explanation:
For a reaction to be double displacement reaction there are two things we need to look for
1) There must be an interchange of the group of ions
2) The reactants must dissolve in water to release ions
A. 2RbNO3 + BeF2 yields Be(NO3)2 + 2RbF
2Rb+ + NO3- + Be^2+ + 2F- → Be(NO₃)₂ + 2RbF
This is correct
B. CaCl + LiCO3 yields CaCO3 + LiCl
This is not correct
The correct equation is:
CaCl2 + Li2CO3 → Ca2+ + 2Cl- + 2Li+ + CO3^2- → 2LiCl + CaCO3
C. Na3PO4 + 3KOH yields 3NaOH + K3PO4
3Na+ + PO4^3- + 3K+ + 3OH- → 3NaOH + K3PO4
This is correct
D. 2MgI2 + Mn(SO3)2 yields 2MgSO3 + MnI4
2Mg^2+ + 4I- + Mn^4+ + 2SO3^2- → 2 MgSO3 + MnI4
This is correct
Explain 1 way compounds of binary ionic and binary covalent substances are similar, as well as 2 ways in which they differ.
Answer:
Answer in explanation
Explanation:
The similarity between binary ionic and binary covalent substances is that they both contain only 2 elements each. This means there are two elements in the configuration of both. That is the similarity between them
Now the first difference I will like to mention is the way in which they are bonded. While ionic substances are formed through the transfer of electrons, covalent substances are formed through the sharing of electrons. This means that an element with an excess number of electrons transfer completely a number of electrons to an element that is deficient in electrons. This can be seen in the case of sodium and chlorine. The electron that is transferred is controlled only by the nucleus of the second electron. In the covalent bonding however, the electrons are shared and the electrons shared are controlled by the nuclei of both elements
Another difference is that while binary ionic compounds might dissolve only in polar solvents such as water, binary covalent compounds might only dissolve in non polar solvents such as benzene.
Answer:
Similarity: they involve the presence of both a cation and an anion.
Differences:
1. Electron giving is done in ionic compounds and electrons sharing is done in covalent compounds.
2. Stronger interactions in ionic compounds while weak interactions in covalent compounds.
Explanation:
Hello,
In this case, one similarity present between ionic and covalent compounds is that both of them involve the presence of both a cation and an anion which are positive and negative respectively; this is in order to allow the contituents to gather by bonding either ionically or covalently.
On the flip side, on the difference is that ionic compounds involve the giving of electrons since usually just the anion attain the octet while the covelent compounds allow electron sharing to allow both the cation and the anion to attain the octet.
Nevertheless, despite the electron sharing and giving fact, ionic compounds have stronger interactions bonding the cation and the anion than those covalent compounds have. Ionic interactions are electrostatic and covalent interactions are attractive which are by far weaker than those electrostatic.
Best regards.
PLEASE HELP!!! NEED TO PASS THIS TO THE FIRST SEMESTER!
Are Reaction 1 and 2 balanced? If the reaction is not balanced, then state how you would balance it. Then, provide the balanced equation.
What kind of reaction does each reaction represents?
Answer:
Reaction 1 is balanced but 2 is not balanced , the balance equation are :
1. [tex]CH_{3}COOH(aq) + NaHCO_{3}(aq)\rightarrow CO_{2}(g) + H_{2}O(l) + CH_{3}COONa(aq)[/tex]
2.[tex]CaCl_{2}(aq) + 2NaHCO_{3}(aq)\rightarrow CaCO_{3}(aq) + H_{2}O(l) + 2NaCl(aq) + H_{2}O(aq)[/tex]
Explanation:
Balanced Equations : These are the equation which follows the law of conservation of mass .
The total number of atoms present in reactant is equal to total number of atoms present in product.
1. [tex]CH_{3}COOH(aq) + NaHCO_{3}(aq)\rightarrow CO_{2}(g) + H_{2}O(l) + CH_{3}COONa(aq)[/tex]
This is acid - base type reaction where
[tex]CH_{3}COOH(aq)[/tex] act as Acid
[tex] NaHCO_{3}(aq)[/tex] act as weak base
Reactant :[tex]CH_{3}COOH(aq)[/tex] ,[tex]NaHCO_{3}[/tex]
Number of atoms of :
C = 2 ([tex]CH_{3}COOH(aq)[/tex]) + 1 ([tex]NaHCO_{3}[/tex])
= 2 + 1
= 3
H = 4([tex]CH_{3}COOH(aq)[/tex]) + 1 ([tex]NaHCO_{3}[/tex])
= 4 + 1
5
O = 2([tex]CH_{3}COOH(aq)[/tex]) + 3 ([tex]NaHCO_{3}[/tex])
= 5
Na = 1 ([tex]NaHCO_{3}[/tex])
= 1
Product : [tex]CO_{2}(g)[/tex],[tex]H_{2}O(l)[/tex] , [tex]CH_{3}COONa(aq)[/tex]
Number of atoms :
C = 1([tex]CO_{2}(g)[/tex]) + 2([tex]CH_{3}COONa(aq)[/tex])
= 1 + 2
= 3
H = 2([tex]H_{2}O(l)[/tex]) + 3([tex]CH_{3}COONa(aq)[/tex])
= 2 + 3
= 5
O = 1([tex]H_{2}O(l)[/tex]) + 2([tex]CH_{3}COONa(aq)[/tex])
+2([tex]CO_{2}(g)[/tex]
= 1 + 2 + 2
= 5
Na = 1([tex]CH_{3}COONa(aq)[/tex]
= 1
Number of Na =1 , C = 3 , H= 5 and O =5 in both reactant and product , so it is a balanced reaction
2.[tex]CaCl_{2}(aq) + 2NaHCO_{3}(aq)\rightarrow CaCO_{3}(aq) + H_{2}O(l) + 2NaCl(aq) + CO_{2}(g)[/tex]
This is double displacement reaction .
Check the balancing in both reactant and products should be :
Na = 2
H = 2
Ca = 1
C = 2
O = 6
Cl = 2
A chemical reaction was run in 210.0 mL of H2O. During the reaction, the temperature of the H2O changes from 27.2 oC to 57.6 oC. How much heat (in kJ) did the chemical reaction produce? For H2O, Cp= 4.184 J/(g · oC). Assume the mass of the solution is 210.0 g. Enter your answer as a positive decimal number.
Answer: The quantity of heat produced by the reaction is +26710.656J
Explanation:
Quantity of Heat, Q = mass * specific heat capacity *temperature change
Q = mCpTc, where m= mass, Cp= specific heat capacity, Tc is temperature change
m= 210.0g, Cp=4.184J/(g · oC), Tc= 57.6 - 27.2 = 30.4 oC
Q = 210.0g *4.184J/(g · oC) * 30.4 oC
Q = +26710.656J
Therefore, the quantity of heat produced by the reaction is +26710.656J.
Note: Even though heat is given out by the system and is normally written as a negative value to indicate that heat is lost, the answer is written as a positive decimal number according to instruction.
PLease help!!! Im in the process of taking my final!!!!! HELPPPPP
An unknown element has 3 rings in its Bohr model. It makes 3 bonds to become stable. It is conductive and shiny, but is not toxic. It is used to build many everyday items. What is the unknown element?
Answer:
The answer to your question is Aluminum
Explanation:
Number of clues
1.- If this element has 3 rings in its Bohr model, we are looking for and element located in the third period of the periodic table.
For example Sodium, Magnesium, Aluminum, Silicate, Phosphorus, Sulfur, Chlorine and, Argon.
2.- It makes three bonds to become stable, then we are looking for and element located in the third group like
Boron, Aluminum, Gallium, Indium, etc
Conclusion
The element that has both characteristics is Aluminum
Consider the reaction: 2 HCl(aq) + Ba(OH)2(aq) BaCl2(aq) + 2 H2O(l); H = –118 kJ. Calculate the change in temperature when 50.0 mL of 0.20 M HCl(aq) and 50.0 mL of 0.10 M Ba(OH)2(aq) are mixed together. The density ofthe solution is 1.00 g/mL and Solution= 4.184 J/g-°C
Answer:
ΔT = 1,41°C
Explanation:
For the reaction:
2HCl(aq) + Ba(OH)₂(aq) → BaCl₂(aq) + 2 H₂O(l); ΔH = –118 kJ.
If moles of reaction are:
HCl:
0,0500L×0,20M = 0,01moles
Ba(OH)₂:
0,0500L×0,10M = 0,005moles
The heat produced is:
0,005mol×-118 kJ/mol = -0,59 kJ = -590 J
The temperature increasing is:
Q = -C×m×ΔT
Where Q is heat (-590 J), m is mass of solution (100mL = 100g -density of 1,00g/mL) and ΔT is change in temperature.
Replacing:
-590J = -4,184J/g°C×100g×ΔT
ΔT = 1,41°C
I hope it helps!
Which of the following chemicals is implicated in both global warming and ozone depletion?a. chlorofluorocarbons b. sulfur dioxide c. nicotine d. radon
Answer:
A
Explanation:
Chlorofluorocarbons generally abbreviated as CFCs are a group of organic chemicals used in several household and industrial materials and are responsible for global warming and ozone depletion.
Global warming is the general increase in the atmospheric temperature of the earth continually over the years. It is a direct consequence of climate change which is caused by the continuous release of green house gases into the atmosphere which trap radiated heat from the sun.
Ozone depletion involves anthropogenic activities which lead to decreasing the natural spread of the ozone layer which prevents the direct contact between the sun UV radiation and the earth.
CFCs are implicated in both cases as they are responsible for the two I.e they cause global warming and also deplete the ozone layer. Years back they are basically used in most aerosol cans like perfumes spray, insecticide spray etc. However as a result of the increased knowledge of their dangers, there had been legislations which had cut down on their continuous usage with alternatives being used
NaCl(aq) AgNO3(aq) → AgCl(s) NaNO3(aq) : NaCl(aq) AgNO3(aq) \rightarrow AgCl(s) NaNO3(aq) : blank H2SO4(aq) 2 LiOH(aq) → 2 H2O(l) Li2SO4(aq) : H2SO4(aq) 2 LiOH(aq) \rightarrow 2 H2O(l) Li2SO4(aq) : blank HCl(aq) (NH4)2S(aq) → H2S(g) 2 NH4Cl(aq) : HCl(aq) (NH4)2S(aq) \rightarrow H2S(g) 2 NH4Cl(aq) : blank Mg(s) Cu(NO3)2(aq) → Mg(NO3)2(aq) Cu(s) :
The question is incomplete, here is a complete question.
Categorize each reaction into types of chemical reactions.
(1) [tex]NaCl(aq)+AgNO_3(aq)\rightarrow AgCl(s)+NaNO_3(aq)[/tex]
(2) [tex]H_2SO_4(aq)+2LiOH(aq)\rightarrow 2H_2O(l)+Li_2SO_4(aq)[/tex]
(3) [tex]HCl(aq)+(NH_4)_2S(aq)\rightarrow H_2S(g)+2NH_4Cl(aq)[/tex]
(4) [tex]Mg(s)+Cu(NO_3)_2(aq)\rightarrow Mg(NO_3)_2(aq)+Cu(s)[/tex]
Answer :
(1) Precipitation reaction
(2) Neutralization reaction
(3) Double-displacement reaction
(4) Single replacement reaction
Explanation :
(1) The balanced chemical reaction is:
[tex]NaCl(aq)+AgNO_3(aq)\rightarrow AgCl(s)+NaNO_3(aq)[/tex]
This reaction is a precipitation reaction in which an insoluble salt formed when two aqueous solutions are combined. The insoluble salt that settle down in the solution is known an precipitate.
(2) The balanced chemical reaction is:
[tex]H_2SO_4(aq)+2LiOH(aq)\rightarrow 2H_2O(l)+Li_2SO_4(aq)[/tex]
This is a neutralization reaction in which an acid react with a base react to give salt and water as a product that means it reacts to give a neutral solution.
(3) The balanced chemical reaction is:
[tex]HCl(aq)+(NH_4)_2S(aq)\rightarrow H_2S(g)+2NH_4Cl(aq)[/tex]
The given reaction is a double-displacement reaction in which the cation of two reactants molecule exchange their places to give two different products.
(4) The balanced chemical reaction is:
[tex]Mg(s)+Cu(NO_3)_2(aq)\rightarrow Mg(NO_3)_2(aq)+Cu(s)[/tex]
This reaction is a single replacement reaction in which the the more reactive element replace the less reactive element.
A sample of gas contains four gases (He, Ne, Ar, and Xe) with the following partial pressures: He (43 mm Hg), Ar (835 mm Hg), and Xe (111 mm Hg). If the total pressure in the container is 1355 mm Hg, what is the partial pressure of Ne in the sample?
To find the partial pressure of Ne in the sample, subtract the sum of the partial pressures of the other gases from the total pressure.
Explanation:To find the partial pressure of Ne in the sample, we need to first determine the partial pressures of all the gases in the mixture. The total pressure in the container is 1355 mm Hg. The partial pressures given are: He (43 mm Hg), Ar (835 mm Hg), and Xe (111 mm Hg).
To find the partial pressure of Ne, we need to subtract the sum of the partial pressures of the other gases from the total pressure.
Partial pressure of Ne = Total pressure - (Partial pressure of He + Partial pressure of Ar + Partial pressure of Xe).
At 700C (1290F), what is the maximum solubility
(a) of Cu in Ag? (
b) Of Ag in Cu?
Answer:
(a) 4 %; (b) 5 %
Explanation:
We need a Cu-Ag phase diagram to answer these questions (see diagram). Yours may differ slightly from the one I used.
(a) Cu in Ag
The horizontal red line at 700 °C cuts the right-hand solvus at about 4 % Ag-96 % Cu.
At this point, copper is in equilibrium with the eutectic.
At 700 °C, the maximum solubility of Cu is about 4 % by mass.
(b) Ag in Cu
The horizontal red line at 700 °C cuts the left-hand solvus at about 5 % Cu-95 % Ag.
At this point, silver is in equilibrium with the eutectic.
At 700 °C, the maximum solubility of Ag is about 5 % by mass.
In this exercise we have to calculate the maximum of each component in the solution:
a) 4%
b) 5%
We need a Cu-Ag phase diagram to answer these questions (see diagram). Yours may differ slightly from the one I used.
(a) Cu in Ag
The horizontal red line at 700 °C cuts the right-hand solvus at about 4 % Ag-96 % Cu.
At this point, copper is in equilibrium with the eutectic.
At 700 °C, the maximum solubility of Cu is about 4 % by mass.
(b) Ag in Cu
The horizontal red line at 700 °C cuts the left-hand solvus at about 5 % Cu-95 % Ag.
At this point, silver is in equilibrium with the eutectic.
At 700 °C, the maximum solubility of Ag is about 5 % by mass.
Learn more: brainly.com/question/16461028
why did mendeleev not order the periodic table by equal rows and columns
Mendeleev organized the periodic table based on atomic mass and chemical properties, deviating from mass order to group chemically similar elements, which allowed him to predict undiscovered elements.
Dmitri Mendeleev did not order the periodic table by equal rows and columns because, during his arrangement of the elements based on their atomic mass, he discovered that placing elements strictly by mass did not result in a table where elements with similar chemical properties were grouped together. Instead, he noticed a pattern of periodicity, where elements showed repeating properties at certain intervals. To maintain this periodicity and to properly organize elements into groups of similar chemical behaviors, he deviated from strict mass order.
For example, he placed iodine after tellurium despite it being lighter, to align it with chemically similar elements. This arrangement also allowed Mendeleev to predict the existence and properties of elements that were undiscovered at the time, based on the gaps and trends in his table. The columns of Mendeleev's periodic table represent groups and the rows represent periods, each row being more massive than the one above it.
1s22s22p63s23p6 How many unpaired electrons are in the atom represented by the electron configuration above?
Answer:
0
Explanation:
There are no unpaired electrons in the given element. It must be noted that for the atom above, we have even numbered electrons. The total electron we are having here is 18.
Now, we must also know that while the s orbital is not degenerate, the P orbital is degenerate. What this mean is that the p orbital is broken down into three different sub orbitals which is the Px , Py and Pz. Hence we can see that there are 6 electrons to enter into the P orbital too.
We can see that all the S orbitals have been completely filled with two electrons alike each. This is also the case for the P orbital as the 3 suborbitals take in 2 each to give a total of six
The number of unpaired electrons in the atom represented by the electron configuration - 1s² 2s² 2p⁶ 3s² 3p⁶ is zero.
Electronic configuration refers to the arrangement of electrons within the atomic orbitals of an atom. It provides a description of how electrons are distributed among the various energy levels and sublevels within an atom.
The electronic configuration is typically represented using a notation that indicates the principal energy level (n) and the sublevel (s, p, d, f) in which the electrons are located. Each sublevel can hold a specific number of electrons: s sublevel holds 2 electrons, p sublevel holds 6 electrons, d sublevel holds 10 electrons, and f sublevel holds 14 electrons.
To determine the number of unpaired electrons, we need to examine the electron configuration in terms of its orbital filling. In this case, all the orbitals up to the 3p sublevel are completely filled with electrons. Neon is an example of a noble gas with a full valence shell, making it stable and unreactive.
Learn more about Electronic configuration, here:
https://brainly.com/question/29184975
#SPJ6
Hydrogen is unique among the elements because ________. 1. It is not really a member of any particular group. 2. Its electron is not at all shielded from its nucleus. 3. It is the lightest element. 4. It is the only element to exist at room temperature as a diatomic gas. 5. It exhibits some chemical properties similar to those of groups 1A and 7A.
Hydrogen is unique due to several factors: it doesn't belong definitively to any group, its electron is unshielded from its nucleus, it is the lightest element, it exists as a diatomic gas at room temperature, and it exhibits properties of both alkali metals and halogens.
Explanation:Hydrogen is indeed unique among the elements for several reasons. Firstly, it is not really a member of any particular group on the periodic table. It is often placed with Group 1A (the alkali metals) because it has one electron in its outer shell like them, but it also exhibits properties similar to Group 7A (the halogens), as it needs one more electron to complete its shell. Secondly, its electron is not at all shielded from its nucleus, resulting in an unusual level of interaction between the two. Thirdly, hydrogen is the lightest element, which impacts its physical and chemical properties. Fourthly, it is the only element to exist at room temperature as a diatomic gas; in its natural state, hydrogen gas (H2) is made up of two hydrogen atoms bonded together. Finally, as already mentioned, it shares chemical properties with both alkali metals and halogens.
Learn more about Unique properties of Hydrogen here:https://brainly.com/question/37190424
#SPJ3
Which one of the following statements is true for an atom that has full s and p orbitals in its outermost energy level?
A. It's highly reactive only with halogens.
B. It has a stable octet and is unreactive.
C. It's highly reactive only with alkali metals.
D. It can be combined with most elements.
Answer:
B. It has a stable octet and is unreactive.
Explanation:
s orbital contains 2 electrons and p contains 6. When the outermost energy level of an element has a total of 8 electrons we call it stable octet and it is unreactive. Therefore the answer is B
Answer:
B.
Explanation:
For example the element with configuration
1s2 2s2 2p6 which is Neon, an inert.
It has a stable 8 electrons in its outermost shell which makes it stable.
According to this decay series chart, which is the proper order of nuclear particle emission that occurs during the transition from lead-214 to lLead-210?
A) Lead-214 changes to bismuth-214.
B) Bismuth-214 changes to polonium-214.
C) Polonium-214 changes to lead-210.
Explanation:
An alpha particles is basically a helium nucleus and it contains 2 protons and 2 neutrons.
Symbol of an alpha particle is [tex]^{4}_{2}\alpha[/tex].
A beta particle is a particle with a negatively charged electron. Symbol of a beta particle is [tex]^{0}_{-1}\beta[/tex].
According to the given question, the decay series chart along with reaction equation are as follows.
(a) Lead-214 changes to bismuth-214.
[tex]^{214}_{82}Pb \rightarrow ^{214}_{83}Bi + ^{0}_{-1}e[/tex]
(b) Bismuth-214 changes to polonium-214.
[tex]^{214}_{83}Bi \rightarrow ^{214}_{84}Po + ^{0}_{-1}e[/tex]
(c) Polonium-214 changes to lead-210.
[tex]^{214}_{84}Po \rightarrow ^{210}_{82} + ^{4}_{2}He[/tex]
Therefore, we can conclude that proper order of nuclear particle emission is beta, beta, alpha.
Calcium carbide crystallizes as a cube with 1 calcium ion on each corner and one calcium ion in the center of the cell. There are 8 carbon atoms located along edges of the cell and there are two carbons internal to the cell. What is the formula of calcium carbide?
Answer:
[tex]CaC_2[/tex]
Explanation:
Given that:-
1 calcium ion is at each corner. Also, 1 corner of the unit cell is shared by 8 unit cubes. So, the share of a tom in one unit cell is:- [tex]\frac{1}{8}[/tex]
Also, there are 8 corners in one unit cell.
So, Total number of atoms at corners = [tex]\frac{1}{8}\times 8[/tex] = 1
Number of calcium atoms in the unit cell = 1
Also, given that there are two carbons which are present internally in the unit cell, So,
Number of carbon atoms in the unit cell = 2
Hence, the formula of the calcium carbide is:- [tex]CaC_2[/tex]
Final answer:
The formula for calcium carbide, given the described crystal structure with calcium ions at the corners and center and carbon atoms along edges and internal to the cell, is CaC2.
Explanation:
To determine the formula for calcium carbide given the crystal structure, we must analyze the arrangement of ions in a unit cell. Each corner atom in the cube is shared among eight unit cells, so only 1/8 of each corner atom actually belongs to one specific unit cell. Since there are eight corner atoms, we can calculate that there is effectively one calcium ion from the corners within one unit cell (8 corners × 1/8 each = 1 calcium ion). Additionally, there is one whole calcium ion at the center of the cell. This means there are two calcium ions per unit cell (1 from corners + 1 from center).
For carbon atoms located along the edges, each one is shared by four unit cells, so only 1/4 of each edge atom is within one unit cell. With 8 edge carbons, this amounts to 2 carbon atoms in total (8 edges × 1/4 each = 2 carbon atoms). Plus, the two entirely internal carbon atoms make for a total of four carbon atoms.
Summing up, there are two calcium ions and four carbon atoms in the unit cell, making the formula for calcium carbide CaC2, since the ratio of calcium to carbon in the unit cell is 2:4, which simplifies to 1:2.