Answer:
D
Explanation:
hope this helps
Answer:
A
Explanation:
Noble gases have a full valence shell, so D is correct.
Inert gases are another term for noble gases, so B is correct.
Noble gases are found in the last column, which is group 18. This makes C correct.
The last one is A, so that must be the one that is incorrect.
I hope this helped and please mark me as brainliest!
67.4 L of sulfur dioxide (SO2) gas at 0.0C and at 1 atm of pressure is equivalent aren’t to how many moles?
Solution here,
Volume(V)=67.4 L
Pressure(P)=1 atm
Temperature(T)=(0+273)K=273K
Universal gas constant(R)=0.0821 L.atm.mol^-1K^-1
No. of moles(n)=?
Now,
PV=nRT
or, 1×67.4=n×0.0821×273
or, 67.4=22.4n
or, n=67.4/22.4
or, n=3
therefore, required no. of mole is 3.
what is the sweetened tea mixture called
Answer:
The sweetened tea mixture is called homogeneous.
The sweetened tea mixture is a homogeneous mixture unlike the heterogeneous mixture which has 2 phases.
What are heterogeneous mixture?Heterogeneous mixtures is defined as a type of mixture where the composition is not uniform throughout the mixture.It consists as two or more phases. The phases are chemically distinct and separate from each other.
As there are two or more phases present in heterogeneous mixtures they can be separated by solvent extraction method where in one phase is miscible with the solvent while the other phase is immiscible.
Components of a heterogeneous mixtures are distinctly visible . There are two types of heterogeneous mixtures, the colloids and the suspensions.These two differ with each other with respect to particle size.It consists of 2 or more phases.
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About how far is it from red bank to Belleville?
Answers:
A) 1 km
B) 10 km
C) 20 km
D) 30 km
Answer:
It would be 30km
Explanation:
The approximate straight-line distance between Red Bank and Belleville, presumably in New Jersey, USA, is about 30 kilometers, making 'option D: 30 km' the correct choice from the given options.
Explanation:The distance between Red Bank and Belleville can vary based on the specific locations in each place, the method of travel, and the route that is chosen. However, to determine the approximate distance between these two locations, one might use a mapping service or tool. Assuming these are the towns in New Jersey, USA, and using a direct path (as the crow flies), the distance is about 30 kilometers. Therefore, out of the options provided, the answer would be option D: 30 km. Note that real-world road distances might be different because roads do not always make straight, direct paths between locations.
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The salt formed from the Acid/ Base reaction between HBr and NaOH is called
The salt formed from the reaction between HBr and NaOH is sodium bromide (NaBr), which is the result of a neutralization reaction involving the combination of hydroxide ions from the base with hydrogen ions from the acid, and the combination of sodium ions from the base with bromide ions from the acid.
The salt formed from the acid/base reaction between HBr (hydrobromic acid) and NaOH (sodium hydroxide) is called sodium bromide (NaBr). When these two reactants combine in a neutralization reaction, the hydroxide ions (OH⁻) from the base react with the hydrogen ions (H⁺) from the acid to produce water (H₂O), and the remaining sodium ions (Na⁺) from the base combine with the bromide ions (Br⁻) from the acid to form the salt sodium bromide (NaBr).
This can be represented by the chemical equation:
NaOH (aq) + HBr (aq) rightarrow NaBr (aq) + H2O (l)
A salt is generally an ionic compound made up of the cation from a base and the anion from an acid. As HBr is a strong acid and NaOH is a strong base, the resulting sodium bromide solution has a neutral pH, similar to sodium chloride (NaCl).
what is the molar mass of Mg(NO3)2
Answer: The molar mass of magnesium nitrate is 148.3148 g/mol.
Explanation:
The molar mass of [tex]Mg(NO_3)_2[/tex] is approximately 148.33 grams/mole.
Calculating the total mass of one mole of the chemical [tex]Mg(NO_3)_2[/tex] (magnesium nitrate) is necessary to determine its molar mass. The molar mass is determined by adding the atomic masses of all the components of the compound, taking into account the value of each subscript.
The elements involved have the following atomic masses:
Magnesium (Mg) = 24.31 grams/mole
Nitrogen (N) = 14.01 grams/mole
Oxygen (O) = 16.00 grams/mole
Magnesium nitrate [tex](Mg(NO_3)_2)[/tex] consists of one magnesium atom (Mg), two nitrate ions [tex](NO^3^-)[/tex], and their respective subscripts.
This formula can be used to obtain the molar mass:
Molar mass of [tex]Mg(NO_3)_2[/tex]= (1 × Mg) + (2 × (N + (3 × O)))
Molar mass of [tex]Mg(NO_3)_2[/tex]= (1 × 24.31) + (2 × (14.01 + (3 × 16.00)))
Molar mass of [tex]Mg(NO_3)_2[/tex]= 24.31 + (2 × (14.01 + 48.00))
Molar mass of [tex]Mg(NO_3)_2[/tex]=24.31 + (2 × 62.01)
Molar mass of [tex]Mg(NO_3)_2[/tex]=24.31 + 124.02
Molar mass of [tex]Mg(NO_3)_2[/tex]= 148.33 grams/mole
Therefore, the molar mass of [tex]Mg(NO_3)_2[/tex] is approximately 148.33 grams/mole.
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Which statement correctly describes measuring with a graduated cylinder?
Answer:
what are the options because a graduated cylinder is a science mixing cylinder is a common piece of laboratory equipment used to measure the volume of a liquid
Explanation:
describe the physical properties of metals, non metals, and metalloids
Metals- • Lustrous (shiny)
• Good conductors of heat and electricity.
• High melting point.
• High density (heavy for their size)
• Malleable (can be hammered)
• Ductile (can be drawn into wires)
• Usually solid at room temperature (an exception is mercury)
• Opaque as a thin sheet (can't see through metals)
Non-metal- • High ionization energies.
• High electronegativities.
• Poor thermal conductors.
• Poor electrical conductors.
• Brittle solids—not malleable or ductile.
• Little or no metallic luster.
• Gain electrons easily.
• Dull, not metallic-shiny, although they may be colorful.
Metalloid-Are generally solids
Can be shiny or dull (luster)May or may not be drawn into wire (ductile)May or may not be hammered flat (malleable)May or may not be brittleConduct heat and electricity better than nonmetals, but not as well as metals Tend to make good semiconductorsHave boiling points that are widely variedHave melting points that are widely variedHave densities that are widely variedMetals are lustrous, malleable, ductile, good conductors of heat and electricity,Non-metals are brittle, dull, and poor conductors of heat and electricity,Metalloids they are shiny, brittle solids with intermediate to relatively good electrical conductivity and the electronic band structure of a semimetal or semiconductor.
What are Metal,Non-metal and Metalloids?Metals are generally shiny, malleable, and hard. Metals are also good conductors of electricity.Non-metals do not conduct heat or electricity very well. Metalloids share characteristics of both metals and non-metals and are also called semimetals.Metals are lustrous, malleable, ductile, good conductors of heat and electricity,Non-metals are brittle, dull, and poor conductors of heat and electricity,Metalloids they are shiny, brittle solids with intermediate to relatively good electrical conductivity and the electronic band structure of a semimetal or semiconductor.
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The density of glycerin is 1.26 Grams/cm^3. How many lbs/ ft is this? Use the conversion rates of 454g/1 lbs and 28317 cm^3/ 1 ft^3 . Express your answer to the correct number of significant figures. The density is .
The answer is:
The density is equal to:
[tex]78.6\frac{lb}{ft^{3} }[/tex]
Why?This a unit conversion problem, so, converting the density of glycerin from [tex]gram/cm^{3}[/tex] to [tex]\frac{lb}{ft^{3}}[/tex] using the given conversion rates, we have:
[tex]1.26\frac{gram}{cm^{3}}*\frac{1lb}{454gram}*\frac{28317cm^{3} }{1ft^{3} }=78.59\frac{lb}{ft^{3} }[/tex]
Rounding to three significant figures, we have that the density is equal to:
[tex]78.6\frac{lb}{ft^{3} }[/tex]
Have a nice day!
The density is 78.6
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all my best girl freinds are offline there not my gf there my best freind i just be pulling a lot of girls
now can u help me with this question Utah is close to an ocean, while New York City is landlocked.
B.
New York City is close to an ocean, while Utah is landlocked.
C.
New York City lies in a rain shadow area.
D.
New York City is closer to mountains.
New York City is close to an ocean and to the great lakes.
Utah is one of the landlocked states.
B. New York City is close to an ocean, while Utah is landlocked.
Thanks
The answer is B. New York City is close to an ocean while Utah is landlocked (landlocked means that it has land on all sides)
If you are confused look at the map below (First pic is Utah and second one is NYC)
Hope this helped!
~Just a girl in love with Shawn Mendes
Correct name for #10 please
Answer:
CH₃CH(CH₃)CH(C₃H₇)CH₂CH(CH₃)₂:
4-isopropyl-2-methylpentane.
Explanation:
Step One: Draw the structure formula of this compound. Parentheses in the formula indicate substitute groups that are connected to the carbon atom to the left.
For example, the first (CH₃) indicates that the second carbon atom from the left is connected to:
the CH₃- on the left-hand side,the -CH(C₃H₇)CH₂CH(CH₃)₂ on the right-hand side,a hydrogen atom, andan additional CH₃- group that replaced one hydrogen atom.Each carbon atom in this compound is connected to four other atoms. All bonds between carbon atoms are single bonds.
The C₃H₇ in the second pair of parentheses is the condensed form of CH₃CH₂CH₂-. See the first sketch attached. Groups in parentheses are highlighted.
Step Two: Find the carbon backbone. The backbone of a hydrocarbon is the longest chain of carbon atoms that runs through the compound. See the second sketch attached. The backbone of this compound consists of seven carbon atoms and is highlighted in green. The name for this backbone shall be heptane.
Step Three: Identify and name the substitute groups.
The two substitute groups are circled in blue in the second sketch.
The one on the right -CH₃ is a methyl group.The one on the left is branched. [tex]\begin{aligned}\text{CH}_3-&\text{CH}-\text{CH}_3\\[-0.5em]&\;|\end{aligned}[/tex] This group can be formed by removing one hydrogen from the central carbon atom in propane. The name for this group is isopropyl.Step Four: Number the atoms.
Isopropyl shall be placed before methyl. Start from the right end to minimize the index number on all substitute groups. The methyl group is on carbon number two and the isopropyl group on carbon number four. Hence the name:
4-isopropyl-2-methylheptane.
the movement of water from ocean through the atmosphere and back
Answer:
Water cycle
Explanation:
The water from the ocean and sea evaporates into the atmosphere and goes into the sky to form clouds.
This turns the liquid water into water vapor in the atmosphere. Plants, too, help water get into the atmosphere through a process called transpiration! After absorbing water from the ground, plants “sweat” water vapor through their leaves to stay cool. Water can also get into the atmosphere from snow and ice.
Can someone help me a will really appreciated. I need help fast i need someone to answer all the questions. You get 10 points
Answer:
1. Theory
2. evidence
3. theory
4. Today, natural sciences are more commonly divided into life sciences, such as botany and zoology; and physical sciences, which include physics, chemistry, geology, astronomy, and materials science.
5.In everyday language a theory means a hunch or speculation. Not so in science. In science, the word theory refers to a comprehensive explanation of an important feature of nature supported by facts gathered over time. Theories also allow scientists to make predictions about as yet unobserved phenomena".
7.Empirical evidence is information acquired by observation or experimentation. Scientists record and analyze this data. The process is a central part of the scientific method
8. Field research is a research conducted in the real world or a natural setting. It tends to observe, analyze, and describe what exists rather than manipulating a factor under study .On the other hand, controlled laboratory research is a research conducted in a setting specifically designed for research
10.You would say Scientific knowledge is always being changed and performed in different ways. Scientific knowledge is always being changed as scientist are experiencing and collecting new information everyday using the scientific method.
6.In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory. It is a misconception that theories turn into laws with enough research.
Which is an acid-conjugate base pair?
Final answer:
An acid-conjugate base pair is when an acid donates a proton to form a conjugate base, or when a base accepts a proton to form a conjugate acid. The strength of an acid is inversely related to the strength of its conjugate base, with strong acids having weak conjugate bases and vice versa.
Explanation:
An acid-conjugate base pair involves a unique relationship in chemical reactions, particularly in the Brønsted-Lowry acid-base theory. In this concept, an acid and a base differ by just one hydrogen ion (H+).
Essentially, if an acid donates an H+ ion, it forms its conjugate base, and if a base accepts an H+ ion, it becomes its conjugate acid.
An example of such a pair is hydrofluoric acid (HF) and fluoride ion (F−), where HF is the parent acid and F− is the conjugate base. Another example is the water molecule (H₂O) acting as a base to form the hydronium ion (H₃O+), its conjugate acid.
A general rule in acid-base chemistry is that the strength of an acid is inversely related to the strength of its conjugate base.
The relative strength of acid-conjugate base pairs is thus an important concept; strong acids have very weak conjugate bases, while strong bases form very weak conjugate acids upon acceptance of a proton.
This relationship helps predict the direction of acid-base reactions and the position of equilibrium.
Final answer:
An acid-conjugate base pair is derived from an acid losing a proton to become its conjugate base; for instance, CH₃CO₂H and CH₃CO₂⁻ make up such a pair. The strength of an acid is inversely related to its conjugate base.
Explanation:
An acid-conjugate base pair consists of two species that differ by the presence or absence of a proton (H+). According to the Brønsted-Lowry theory, an acid is a proton donor and a base is a proton acceptor. When an acid donates a proton, it becomes its conjugate base, and when a base accepts a proton, it becomes its conjugate acid. For example, when we take the acetic acid (CH₃CO₂H) and it donates a proton (H+), it forms the acetate ion (CH₃CO₂⁻), making CH₃CO₂H and CH₃CO₂⁻ a conjugate acid-base pair. Similarly, water (H₂O) can accept a proton to become hydronium (H₃O+), creating the conjugate acid-base pair H₂O and H₃O+.
The relative strength of an acid and its conjugate base is inversely related: the stronger the acid, the weaker the conjugate base, and vice versa. Therefore, the conjugate base of a strong acid like hydrochloric acid (HCl) is a weaker base (Cl⁻), and the conjugate acid of a strong base like hydroxide (OH⁻) is a weaker acid (H₂O).
Which best describes why governmental funding for scientific research is
important?
A. Governmental funding always determines what a scientist thinks
is right and wrong.
O
B. Governmental funding provides more money than private funding.
C. Governmental funding provides a way to control what kind of
scientific research is done.
D. Governmental funding guarantees that all scientific research will
help everyone
I think C is the perfect answer. This is because if the govermental funding do not provide a way to control the scientific research, then scientists might done their jobs illegally as they can do anything to complete their experiment and research.
Answer:
Explanation:
Specifically, scientific research can be defined as an activity developed by researchers, aiming at new discoveries and thus contributing to the quality of intellectual life. Still, the research includes some of the activities developed during academic life, which requires from the researcher some skills necessary for the full development of their functions, such as planning, knowledge and adaptation to scientific norms.
Scientific research is very important for the development of the country, and for a scientific research to be completed and to achieve good results, this research needs funding, to buy equipment and other elements necessary for the research to be carried out. It is very important for research to receive government funding, as government usually provides more funding than private companies, especially in research done in underdeveloped countries.
What mass of carbon dioxide (CO2) will be produced if 2.90 moles of iron (Fe) is produced?
Answer:
191.4 g.
Explanation:
The balanced equation for the mentioned reaction is:Fe₂O₃(s) + 3CO(g) → 2Fe(s) + 3CO₂(g),
It is clear that 1.0 mole of Fe₂O₃ react with 3.0 mole of CO to produce 2.0 moles of Fe and 3.0 moles of CO₂.
Using cross multiplication:
2.0 mol of Fe produced with → 3.0 mol of CO₂, from stichiometry.
2.9 mol of Fe produced with → ??? mol of CO₂.
∴ The no. of moles of CO₂ produced = (3.0 mol)(2.9 mol)/(2.0 mol) = 4.35 mol.
∴ The mass of CO₂ produced = no. of moles x molar mass = (4.35 mol)(44.0 g/mol) = 191.4 g.
measles is a disease that causes fever and rash the graph gives the number of measles causes in the US between 1954 and 2008 the measles vaccine was introduced in 1960. What can you conclude using the info on a graph
The introduction of the measles vaccine in the US in 1960 led to a significant decrease in the number of measles cases.
Explanation:The information on the graph shows the number of measles cases in the US between 1954 and 2008. The graph shows that the measles vaccine was introduced in 1960. From the graph, we can conclude that the introduction of the measles vaccine led to a significant decrease in the number of measles cases in the US. Prior to the vaccine, there were fluctuating numbers of cases, but after the vaccine was introduced, the number of cases dropped to almost zero.
12. The most common factors that cause chemical reactions to occur are all the following except
[A] transfer of electrons [B] formation of a solid
[C] formation of water
[D] formation of a gas
[E] a decrease in temperature
A decrease in temperature [E] is generally not a cause of chemical reactions. Other factors like the transfer of electrons, formation of a solid, water or gas are common causes.
Explanation:The most common factors that can cause chemical reactions to occur include the transfer of electrons, formation of a solid, formation of water, and formation of a gas. However, the option that does not generally cause a chemical reaction to occur is a decrease in temperature [E]. In fact, an increase in temperature typically facilitates chemical reactions as it increases the energy of the particles involved, making them more likely to react.
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Most commonly, chemical reactions occur due to the transfer of electrons, the formation of a solid, the formation of water, or the formation of a gas. A decrease in temperature is not typically a factor that facilitates chemical reactions.
Explanation:The most common factors that cause chemical reactions to occur include the transfer of electrons, the formation of a solid, the formation of water, and the formation of a gas. These actions involve breaking and forming chemical bonds that result in new substances. However, a decrease in temperature is typically not a factor that causes chemical reactions. In fact, an increase in temperature is more likely to cause a chemical reaction as it provides the necessary energy for the particles to react.
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Acid rain is represented by the formula H2SO4. How many atoms of sulfur are present in one molecule of acid rain?
One
Two
Four
Six
Answer: A. one atom
Explanation: i did some research on it and that is what i found.
One molecule of H₂SO₄ comprises one atom of sulfur. Thus, option A is correct.
What is acid rain?Acid rain is given as the precipitation that has been comprising the chemical compound acidic in nature, thereby the pH of the precipitation as well.
The number of atoms in a molecule can be determined with the chemical formula. The subscript to an element in the formula is corresponding to the number of atoms of element present in the molecule or atom.
In the molecule of H₂SO₄, the subscript number to the hydrogen atom is 2, thereby 2 hydrogens are present, and the subscript to the sulfur is the representation of the number of atoms of sulfur in the molecule that stands for 1.
Therefore, 1 atom of sulfur is present in the molecule of H₂SO₄. Thus, option A is correct.
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How many grams are there in 5.0×1024 formula units of ammonia
Answer:
141.1g
Explanation:
The formula of ammonia is written as NH₃
Given parameters:
Number of particles = 5.0 x 10²⁴atoms
To calculate the mass of the substances that makes up this number of ammonia particles, we follow use the mole concept to derive it.
1. We know that a mole is the amount of a substance that contains the Avogadro's number of particles i.e 6.02 x 10²³
From this, we can then derive the number of moles using the expression below:
Number of moles =
number of particles/6.02 x 10²³
2. With the number of moles, we can deterime the mass using the expression below:
Number of moles= mass/molar mass
Mass(g) = number of moles x molar mass
Solution
From step 1:
Number of moles = 5.0 x 10²⁴ / 6.02 x 10²³
No of moles of NH₃ = 0.83 x 10 = 8.3mol
Step 2:
Molar mass of NH₃:
Atomic mass of N = 14gmol⁻¹
H = 1gmol⁻¹
Molar mass = 14 + (1x3) = 17gmol⁻¹
Using the expression:
Mass(g) = number of moles x molar mass
Mass of NH₃ = 8.3 x 17 = 141.1g
A train is traveling at 50.0 miles per hour 1 mile is equal to 1.61
kilometers. How fast is the train moving in meters per second?
m/s
Answer:
The train is moving at the speed of 22.36 meters per second
Explanation:
Speed of the train = 50 .0 miles/hour
1 mile = 1.61 km
50 miles = [tex]50.0\times 1.61 km=80.5 km[/tex]
1 km = 1000 m
1 hour = 3600 seconds
So,the speed of the train in meter per seconds:
[tex]=\frac{80.5\times 1000 m}{3600 s}=22.36 m/s[/tex]
Is freshly squeezed grapefruit juice a homogeneous or heterogeneous mixture?
Answer:
Homogeneous because if you were to take a sip it would be the same all throughout the juice, nothing changes. Hope this helped, please mark me the brainliest answer? Have a good day :)
Answer:
Explanation:
heterogeneous
how many molecules are in 3.6 grams of NaCl?
To find the number of molecules in 3.6 grams of NaCl, convert the grams to moles of NaCl using its molar mass and then multiply the number of moles by Avogadro's number (6.02 x 10^23). The result is approximately 3.7 x 10^22 molecules.
Explanation:To find out how many molecules are in 3.6 grams of NaCl, first calculate the number of moles of NaCl. Each mole of NaCl has a mass of 58.44 grams (sum of atomic masses of Na and Cl). So, 3.6 grams corresponds to 3.6/58.44 = 0.0616 moles.
Now, use the Avogadro's number which states that one mole of any substance contains 6.02 x 10^23 molecules. So, 0.0616 moles of NaCl would contain approximately 0.0616 x 6.02 x 10^23 = 3.7 x 10^22 molecules.
In conclusion, the number of molecules in 3.6 grams of NaCl is approximately 3.7 x 10^22.
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To find the number of molecules in 3.6 grams of NaCl, first calculate the number of moles (0.0615 moles), then convert this to molecules using Avogadro's number, resulting in approximately 3.70 x 10²² molecules.
To determine the number of molecules in 3.6 grams of NaCl, follow these steps:
Calculate the molar mass of NaCl: The molar mass of NaCl is the sum of the atomic masses of sodium (Na) and chlorine (Cl). Thus, the molar mass of NaCl is 23.0 g/mol (Na) + 35.5 g/mol (Cl) = 58.5 g/mol.Find the number of moles in 3.6 grams of NaCl: Use the formula: number of moles = given mass / molar mass.Number of moles of NaCl = 3.6 g / 58.5 g/mol ≈ 0.0615 moles
Convert moles to molecules: Use Avogadro's number, which is 6.022 x 10²³ molecules per mole.Number of molecules = 0.0615 moles x 6.022 x 10²² molecules/mole ≈ 3.70 x 10²² molecules
Therefore, there are approximately 3.70 x 10²² molecules in 3.6 grams of NaCl.
A contour line connects points of the same _____.
A. latitude
B. longitude
C. elevation
D. rock type
Answer:
the answer is elevation
Answer: C. Elevation
Which of the following is a non metal that remains liquid at room temperature?
A. Phosphorous
B. Bromine
C. Chlorine
D. Helium
Chlorophyll is a naturally occurring chelate compound in which central metal is
A. copper
B. magnesium
C. iron
D. calcium
Answer:
1st answer B. Bromine
2nd answer B. magnesium
Explanation:
Hello There!
Which of the following is a non metal that remains liquid at room temperature? "OPTION B"
Chlorophyll is a naturally occurring chelate compound in which central metal is "OPTION B"
What is the pH of a solution that has a hydroxide ion concentration of 1.0×10−9 M?
Answer:
[tex]\boxed{\text{pH = 5.00}}[/tex]
Explanation:
Step 1. Calculate the pOH
pOH =-log[OH⁻]
pOH =-log(1.0 × 10⁻⁹)
pOH = 9.00
Step 2. Calculate the pH
pH + pOH = 14.00
pH + 9.00 = 14.00
[tex]\boxed{\textbf{pH = 5.00}}[/tex]
Final answer:
The pH of a solution with a hydroxide ion concentration of 1.0 × 10⁻⁹ M is 5, indicating the solution is acidic.
Explanation:
To calculate the pH of a solution with a known hydroxide ion concentration, we can use the relationship between the concentration of hydroxide ions ([OH-]) and hydrogen ions ([H+]), which is given by the ionic product of water (Kw = 1.0 × 10⁻¹⁴ at 25°C). The pH is defined as the negative logarithm of the hydrogen ion concentration, pH = -log([H+]).
Since we have the hydroxide ion concentration ([OH-] = 1.0 × 10⁻⁹ M) we can find the hydrogen ion concentration from Kw:
Kw = [H+] × [OH-]
[H+] = Kw / [OH-]
[H+] = (1.0 × 10⁻¹⁴ M2) / (1.0 × 10⁻⁹ M)
[H+] = 1.0 × 10-5 M
Now we can calculate the pH:
pH = -log([H+])
pH = -log(1.0 × 10⁻⁵)
pH = 5
A pH of 5 indicates that the solution is acidic, as a pH less than 7 is characteristic of an acidic solution.
The Lewis dot notation for two atoms is shown.
Na is written with a dot on its right. Cl is written on the right of Na. There are seven dots around Cl. An arrow points from the dot near Na to Cl.
What is represented by this notation?
Explanation:
Atomic number of sodium is 11 and its electronic distribution is 2, 8, 1. So, it means there is only one valence electron present in a sodium atom. This valence electron is represented by a dot in the Lewis structure.
Atomic number of chlorine is 17 and its electronic distribution is 2, 8, 7. So, it means there are seven valence electrons present in a chlorine atom. These valence electrons are represented by seven dots in the Lewis structure.
Also, in order to attain stability sodium will lose one valence electron and this valence electron will be gained by chlorine atom.
Therefore, an arrow pointed from dot near Na to Cl shows that an electron is being donated from Na to the Cl atom.
In an endothermic physical or chemical change,.
A)the potential energy of the system increases
B)all of these
C)the system absorbs heat from its surroundings
D)kinetic energy is converted into potential energy and seems to disappear
Answer:
c
Explanation:
If chemical equation neads heat to happen it's caled endothermic
eg. CaCO3 ---> CaO + CO2 (there is supposed to be a little t above the arrow)
Endothermic reactions are chemical reactions in which the reactants absorb heat energy from the surroundings to form products. Hence, option C is correct.
What is an endothermic reaction?Endothermic reactions are chemical reactions in which the reactants absorb heat energy from the surroundings to form products
In an endothermic reaction, the products are higher in energy than the reactants.
Therefore, the change in enthalpy is positive, and heat is absorbed from the surroundings by the reaction.
Hence, option C is correct.
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Justin mixed two clear liquids together during an experiment and made the following observations:
The mixed liquids decreased in temperature without any refrigeration or other action to change the temperature.
The color of the liquid changed to blue.
Which statement best describes Justin’s experiment?
A.
A physical change occurred, and this caused the liquid’s chemical properties to change.
B.
A chemical change occurred, and this caused the liquid’s physical properties to change.
C.
A physical change occurred, so only physical properties changed.
D.
A chemical change occurred, so only chemical properties changed.
Answer:
B. A chemical change occurred which caused the liquid's physical properties to change.
Explanation:
The reduction of the temperature of the system meant that the reaction absorbed heat energy from it. This shows that a chemical reaction was in progress. New products were formed, and this is proved by the change in the color to blue.
Answer: Option (B) is the correct answer.
Explanation:
A chemical reaction in which energy is absorbed by the reactant molecules is known as endothermic reaction. In this type of reaction there occurs decrease in temperature.
For example, Justin mixed two clear liquids together during an experiment and he noticed that decrease in temperature occurs without any refrigeration or other action to change the temperature.
Then it means an endothermic reaction has occurred.
Sometimes, chemical changes also leads to change in color of the reaction mixture.
Whereas a chemical reaction in which energy is released by the reactant molecules is known as exothermic reaction. In this type of reaction there occurs an increase in temperature.
A physical change is that change which does not lead to any difference in chemical properties of a substance.
For example, mass, density, etc are all physical properties.
On the other hand, a chemical reaction is that change which leads to change in chemical properties of a substance.
For example, combustion, toxicity, etc are all chemical properties.
Thus, we can conclude that the statement a chemical change occurred, and this caused the liquid’s physical properties to change, best describes Justin’s experiment.
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Why would a pendulum stop swinging? Where did the energy go?
Answer:
The pendulum would stop swinging because the kinetic energy would slow down for the friction is causing it to slow. The energy would go into potential energy.
Answer:
friction/heat
Explanation:
the pendulum would eventually stop swinging dude to friction in the air. the friction makes heat even if it is the smallest amount it is still energy. the pendulum would eventually stop due to friction which makes heat
explain what happens in a nuclear chain reaction
Answer:
Nuclear Chain Reactions. A chain reaction refers to a process in which neutrons released in fission produce an additional fission in at least one further nucleus. This nucleus in turn produces neutrons, and the process repeats. The process may be controlled (nuclear power) or uncontrolled (nuclear weapons).
Explanation:
A nuclear chain reaction occurs when an initial reaction causes more reactions, generating recurring secondary reactions, forming a self-sustaining chain, much like a domino effect. This process is common in nuclear fission and fusion.
Explanation:In a nuclear chain reaction, an initial reaction causes excess neutrons to be emitted. These neutrons then cause other similar nuclear reactions, generating more neutrons and thus, more nuclear reactions. This sequence forms a self-sustaining chain. This is common in both nuclear fission, as seen in nuclear power plants and atomic bombs, or in a controlled manner in nuclear fusion, as is being researched for future clean energy solutions. It's like a domino effect but with atomic nuclei and neutrons.
Learn more about Nuclear Chain Reaction here:https://brainly.com/question/31662743
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