432 inches
Each project is 9 feet, and she is making 4 projects, so multiply 9 by 4 to find the number of feet needed. You should get 36. Each foot is equal to 12 inches, so multiply 36 by 12 to get 432 inches.
Answer: 432 inches
Explanation:
Given : length of ribbon needed by Shannon for an art project = 9 feet
As we know : 1 feet = 12 inches
9 feet =[tex]\frac{12}{1}\times 9=108inches[/tex]
Thus if for 1 project , length of ribbon required is = 108 inches
For 4 projects , length of ribbon required is =[tex]\frac{108}{1}\times 4=432inches[/tex]
Thus 432 inches of ribbon should she buy if she is making 4 projects.
HELP PLS !!!! :))Formula unit of Sr and CI
Formula unit of AI and S
Answer : The formula unit of Sr & Cl is [tex]SrCl_2[/tex] and the formula unit of Al & S is [tex]Al_2S_3[/tex]
Explanation :
Formula unit : it is defined as the lowest number ratio of ions of an elements in an ionic compound or covalent compound.
For the formula unit of Sr & Cl, two chloride ions[tex](Cl^-)[/tex] are needed to neutralize the one strontium ion[tex](Sr^{2+})[/tex].
For the formula unit of Al & S, three sulfide ions[tex](S^{2-})[/tex] are needed to neutralize the two aluminium ion[tex](Al^{3+})[/tex].
The formula unit of [tex]SrCl_2[/tex] and [tex]Al_2S_3[/tex] are shown below.
In a certain organic compound, one of the carbon atoms is bonded to three atoms. One of these is a carbon atom and the other two are hydrogen atoms. What type of bond exists between the two carbon atoms?
Double Covalent
Ionic
Ion Dipole
Since the C is bonded to 2 H atoms,
it needs two more bonds to complete the octet of C(as C forms four bonds in total),hence C-C bond is double covalent bond
The bonded C atom is shown as bold C here:
-C=CH2
The bond between the two C atoms is Double Covalent.
The type of bond that exists between the two carbon atoms in this organic compound is a double covalent bond.
In a double covalent bond, two pairs of electrons are shared between the two carbon atoms. Each carbon atom contributes one electron from its outermost electron shell to form a strong and stable bond. This sharing of electrons allows both carbon atoms to satisfy the octet rule, which states that atoms tend to gain, lose, or share electrons to achieve a stable configuration with a full outer electron shell, typically containing eight electrons.
Covalent bonds occur when atoms share electrons to achieve a stable electron configuration. In the case of a double covalent bond, there are two pairs of shared electrons between the two carbon atoms. This bond is strong and requires a significant amount of energy to break, making it a key characteristic of many organic compounds with double bonds, such as alkenes and some functional groups in organic chemistry.
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PLEASE HELP ASAP!! CHEMISTRY BALANCING EQUATIONS!
How many liters of NH3 at stp will react with 5.3g O2 to form NO2 and water?
4NH3(g) + 7O2(g) -> 4NO2 + 6H2O(g)
A. 0.00423L
B. 2.12L
C.3.03L
D. 6.49L
Answer:
B. 2.12 L
Step-by-step explanation:
We know we will need a balanced chemical equation with masses and molar masses, so, let's gather all the information in one place.
M_r: 32.00
4NH₃(g) + 7O₂(g) ⟶ 4NO₂ + 6H₂O(g)
m/g: 5.3
(a) Moles of O₂
Moles of O₂ = 5.3 × 1/32.00
Moles of O₂ =0.166 mol
=====
(b) Moles of NH₃
The molar ratio is 4 mol NH₃= 7 mol O₂.
Moles of NH₃ = 0.166 × 4/7
Moles of NH₃ = 0.0946 mol NH₃
=====
(c) Volume of NH₃ at STP
STP is 1 bar and 0 °C. At STP, the molar volume of a gas is 22.71 L.
Volume of NH₃ = 0.0946 ×22.71/1
Volume of NH₃ = 2.15 L
=====
It looks as if you are using the old (pre-1982) definition of STP.
Under that definition, the molar volume of a gas at STP was 22.41 L.
The volume of NH₃ is then 2.12 L.
Given that Cu + 2HCI Cu2+ + 2CI- + H2(g) has an overall reduction potential of –0.34 V, what is a valid prediction about how this reaction works? The reaction is not spontaneous and will require energy to proceed. The reverse reaction would require energy input in order to occur. The half reactions would both occur spontaneously. The reaction is not spontaneous, and it is impossible to make it occur.
Cu + 2HCI → Cu²⁺ + 2CI⁻ + H2(g)
has an overall reduction potential of –0.34 V
The correct option is:
The reaction is not spontaneous and will require energy to proceed.
Since the overall reduction potential is negative,the reaction is not spontaneous and it requires energy to proceed.
The reaction is
Cu(s) + 2HCI(aq) ---> Cu⁺² + 2CI⁻ + H₂(g)
The given E⁰cell = -0.34
The overall reduction potential is negative
A reaction is said to be spontaneous it is ΔG° is negative
The relation between ΔG° and Electrode potential is
ΔG° = -nFE°cell
as given that
E°cell = -0.34 V
The overall value of ΔG° will be positive and hence reaction must be non spontaneous
so
The reaction is not spontaneous and will require energy to proceed.
Two electrons are found in the same atom. One has the quantum number set (3, 2, 0, +?), and the other has the quantum number set (3, 1, 0, +?). They share thea same sub level but differentt orbitalsb same orbital but different spin directionsc same energy level but different sublevelsd same type of sub level but found in different energy sub levels
D. Same energy level but different sublevel.
ExplanationThere are four quantum numbers [1]:
n, the principal quantum number,l, the orbital angular momentum quantum number,[tex]m_l[/tex], the magnetic quantum number, and[tex]m_s[/tex], the electron spin quantum number.As their names might suggest:
n determines the main energy level of an electron. l determines the type of sublevel of an electron.Each sublevel might contain more than one orbital. [tex]m_l[/tex] gives the orbital of an electron.Each orbital contains up to two electrons. [tex]m_s[/tex] tells two electrons in the same orbital apart.The two electrons in question come from the same atom. The question suggests that they have the same n, [tex]m_l[/tex], and [tex]m_s[/tex]. As a result, both electrons are in main energy level n = 3. They share the same spin.
However, the two electrons differ in their value of l.
l = 2 for the first electron. It belongs to a d sublevel. l = 1 for the second electron. It belongs to a p sublevel. Reference[1] Kamenko, Anastasiya, et. al, "Quantum Numbers", Physical & Theoretical Chemistry, Chemistry Libretexts, 24 Mar 2017.
When 25.0 grams of water are cooled from 20.0 degrees Celsius to 10.0 degrees Celsius the number of joules of heat energy released is?
Heat energy released here
Q = mass x specific heat capacity of water x deltaT
= 25.0 x 4.184 x (-10.0)
= - 1046 Joules
1046 Joules of heat energy is released in this process.
Answer: The amount of heat released is -1046 J
Explanation:
To calculate the amount of heat released, we use the equation:
[tex]q=mc\Delta T[/tex]
where,
q = heat released = ?
m = mass of water = 25.0 g
c = specific heat capacity of water = 4.184 J/g.°C
[tex]\Delta T[/tex] = change in temperature = [tex]T_2-T_1=(10.0-20.0)^oC=-10.0^oC[/tex]
Putting values in above equation, we get:
[tex]q=25.0g\times 4.184J/g.^oC\times (-10.0^oC)\\\\q=-1046J[/tex]
Hence, the amount of heat released is -1046 J
Help me number 16 and 17
16) Chemical equation: Ca + H₃PO₄ → Ca₃(PO₄)₂ + H₂.
Oxidation reaction: Ca⁰ → Ca⁺² + 2e⁻ /×3.
3Ca⁰ → 3Ca⁺² + 6e⁻
Reduction reaction: 6e⁻ + 2H₃⁺¹ → 3H₂⁰.
Calcium change oxidation number from 0 to +2 (oxidation) and hydrogen change oxidation number from +1 to 0 (reduction).
Balanced chemical equation: 3Ca + 2H₃PO₄ → Ca₃(PO₄)₂ + 3H₂.
Calcium is stronger reducing agent than hydrogen, gives electrons easier.
This is example of single displacement reaction.
Single displacement is reaction where neutral element metal or nonmetal become an ion as it replaces another ion in a compound.
17) Balanced chemical equation:
3Ca(s) + 2H₃PO₄(aq) → Ca₃(PO₄)₂(aq) + 3H₂(g).
Ionic equation: 3Ca + 6H⁺ + 2PO₄³⁻ → 3Ca²⁺ + 2PO₄³⁻ + 3H₂.
Net ionic equation: 3Ca + 6H⁺ → 3Ca²⁺ + 3H₂.
A spectator ion is an ion that exists as a reactant and a product in a chemical equation.
A spectator ion is phospate anion PO₄³⁻.
A plane traveling at 80m/s lands on a runway and comes to rest after 10 seconds. What was the planes deceleration?
The molarity (M) of an aqueous solution containing 29.8 g of sucrose, C12H22O11, in 120 mL of solution is:
2.58 x 10–2 M.
7.26 x 10–4 M.
1.38 M.
0.726 M.
Answer:
0.726 mol·L⁻¹
Step-by-step explanation:
c = moles/litres
=====
Moles = 29.8 × 1/342.30
Moles = 0.087 06 mol
=====
Litres = 120 × 1/1000
Litres = 0.120 L
=====
c = 0.087 06/0.120
c = 0.725 mol·L⁻¹
*explain answer for brainliest
Which of the following is a valid mole ratio from the balanced equation 2Fe2O3 + 3C → 4Fe + 3CO2?
two moles of F e two O three over four moles of F e
four moles of C over three moles of F e
two moles of F e two O three over four moles of C
three moles of C over four moles of C O two
Answer:
2 mol Fe₂O₃/ 4 mol Fe
Step-by-step explanation:
The balanced equation is
2Fe₂O₃ + 3C → 4Fe + 3CO₂
The molar ratio uses the coefficients of the formulas in the balanced equation.
Those in front of Fe₂O₃ and Fe are 2 and 4, respectively.
B is wrong. the correct ratio is 3 mol C/4 mol Fe.
C is wrong. The correct ratio is 2 mol Fe₂O₃/3 mol C.
D is wrong. The correct ratio is 3 mol C/3 mol CO₂.
What is the momentum of a 750-kg car traveling at a velocity of a 25 m/s?
Momentum = mass x velocity 750x25 = 18750 kg-m/s.
How are natural polymers and synthetic polymers similar?
A) Both are made up of phosphates and organic bases
B) Both serve important roles in producing amino acids
C) Both are made up of monomers that are linked by covalent bonds
Answer: C) Both are made up of monomers that are linked by covalent bonds
Explanation: Polymers are large molecules which are formed by combination of small repeating units called as monomers.
Natural polymers are found in nature such as cellulose whereas synthetic polymers are synthesized in laboratories such as Nylon 6,6.
All the polymers, whether natural or synthetic are made up of monomers and are joined by covalent bonds.
Both natural and synthetic polymers consist of monomers that are linked together by covalent bonds, with natural polymers having a wider variety of monomers like amino acids, and synthetic polymers often containing fewer types of monomers. Option C is correct .
Natural polymers and synthetic polymers are similar in that they are both made up of monomers linked together by covalent bonds. Examples of natural polymers include proteins and DNA, which are fundamental to biological structure and function. Synthetic polymers, on the other hand, include plastics like polystyrene. Option C is correct .
The monomers in natural polymers can vary greatly; there are 20 different amino acids that can combine in a multitude of sequences to form different proteins. Synthetic polymers typically feature fewer types of monomers, but the process of polymerization, which results in the formation of large molecules through the joining of these monomers, is a common characteristic shared by both natural and synthetic polymers.
Proteins are significant examples of natural polymers, functioning as enzymes that catalyze biological reactions. While synthetic polymers do not serve in biological catalysis, their repeating monomer units confer them with unique physical properties making them valuable in a variety of applications.
Sulfuric acid is essential to dozens of important industries from steelmaking to plastics and pharmaceuticals. More sulfuric acid is made than any other industrial chemical, and world production exceeds 2.0 x 10 kg per year. The first step in the synthesis of sulfuric acid is usually burning solid sulfur to make sulfur dioxide gas. Suppose an engineer studying this reaction introduces 4.4 kg of solid sulfur and 6.90 atm of oxygen gas at 950. °C into an evacuated 50.0 L tank. The engineer believes K-0.71 for the reaction at this temperature. Calculate the mass of solid sulfur he expects to be consumed when the reaction reaches equilibrium. Round your answer to 2 significant digits. Note for advanced students: the engineer may be mistaken in his belief about the value of Kp, and the consumption of sulfur you calculate may not be what he actually observes.
Given:
K = 0.71 = Kp
The reaction of sulphur with oxygen is
S(s) + O2(g) ---> SO2(g)
initial Pressure 6.90 0
Change -x +x
Equilibrium 6.90-x x
Kp = pSO2 / pO2 = 0.71 = x / (6.90-x)
4.899 - 0.71x = x
4.899 = 1.71x
x = 2.86 atm = pressure of SO2 formed
temperature = 950 C = 950 + 273.15 K = 1223.15 K
Volume = 50 L
Let us calculate moles of SO2 formed using ideal gas equation as
PV = nRT
R = gas constant = 0.0821 L atm / mol K
putting other values
n = PV / RT = 2.86 X 50 / 1223.15 X 0.0821 = 1.42 moles
Moles of Sulphur required = 1.42 moles
Mass of sulphur required or consumed = moles X atomic mass of sulphur
mass of S = 1.42 X 32 = 45.57 grams or 0.04557 Kg of sulphur
HURRY! 10 POINTS!!
Identify the correct statement regarding the strength of chemical bonds.
A. Strong bonds form with large atoms and weak bonds with small atoms.
B. Weak bonds require less energy to form than strong bonds.
C. Strong bonds occur with high temperature and weak bonds with low temperature.
D. Weak bonds require more energy to form than strong bonds.
Answer:
The answer is D, weak bonds require more energy to form than strong bonds.
Explanation:
The correct answer is option B: Weak bonds require less energy to form than strong bonds. This is because the strength of a chemical bond is related to the energy required to break it, not the energy required to form it.
Explanation:The correct statement regarding the strength of chemical bonds is option B: Weak bonds require less energy to form than strong bonds. The strength of a chemical bond is related to the energy required to break it, not the size of the atoms, temperature, or energy required to form it. A strong bond has a high bond energy because it requires a great deal of energy to break. Conversely, a weak bond, which requires relatively little energy to break, has a low bond energy. This suggests that strong bonds do indeed require more energy to form than weak bonds.
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The element bromine, Br, has a larger atomic radius than A) Cu, O and Ba B) I, Cu, and Ba C) F and Kr D) O, F, and Kr
The answer is: D) O, F, and Kr.
Atomic radius of bromine (Br) is 114 pm.
Atomic radius of oxygen (O) is 73 pm.
Atomic radius of fluorine (F) is 72 pm.
Atomic radius of krypron (Kr) is 112 pm.
The atomic radius of a chemical element is a measure of the size of its atom.
The atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.
The atomic radius decreases across the periods because an increasing number of protons, because greater attraction between the protons and electrons.
Substances have more kinetic energy in the _______ state than in the _______ state. A. Gas; solid B. Solid; gas C. Solid; liquid D. Liquid; gas
Answer: gas and then solid.
Explanation: Just trust me ok.
Generally, when going down a group on the periodic table:
atomic radii decrease
ionic radii increase
electronegativity increases
reactivity decreases
Generally when we move down the group on a periodic table the atomic radii increases as the valency electrons occupy higher levels due to the increasing quantum number. Hence the atomic radii increases down the group.
The ionic radii increases down the group because while we move down the group the elements gain electrons and form ions called anions as an additional electron occupies the orbital the ions get bigger in size. Hence the ionic radii increase.
Electronegativity is described as the ability to attract and bind with electrons and it is a qualitative property. It decreases as we move down the group because the distance between the valency electrons and the nucleus increases. Hence electronegativity decreases down the group.
Reactivity increases as we move down the group as the metals have the tendency to lose electron form its outer shell.
Therefore the answer is ionic radii increases.
The modern atomic model is sometimes called the ________, or quantum mechanics model.
The modern atomic model is sometimes called the electron cloud , or quantum mechanics model.
So the answer is electron cloud
The answer to this question should be electron cloud.
You're conducting an experiment to determine the effect of different wavelengths of light on the absorption of carbon dioxide as an indicator of the rate of photosynthesis in aquatic ecosystems. If the rate of photosynthesis increases, the amount of carbon dioxide in the environment will decrease, and vice versa. Small aquatic plants are placed into three containers of water mixed with carbon dioxide. Container A is placed under normal sunlight, B under green light, and C under red light. The containers are observed for a 24-hour period. Carbon dioxide absorption is an appropriate indicator of photosynthesis because
The process of formation of sugar or carbohydrate by plants is known as photosynthesis.
It occurs in presence of light so the term "photo"
Here the plant uses carbon dioxide and it reacts with water to given glucose
The general reaction will be
6CO2(g) + 6H2O(g) + sunlight ---> C6H12O6 + 6O2
Thus the carbon dioxide is being converted to glucose
Higher the rate of absorption of carbon dioxide by plant more the rate of formation of glucose or more the rate of photosynthesis by the plant
The formation of glucose from carbon dioxide is a metabolic pathway which is a cycle known as Calvin cycle. Here actually the carbon is fixed into useful carbohydrates and this pathway is light independent.
Hence
Carbon dioxide absorption is an appropriate indicator of photosynthesis because the main part of photosynthesis if fixation of carbon dioxide into useful carbohydrates by Calvin cycle (occurs in chloroplast of plant cells)
A solution is made by dissolving 1.00 moles of sodium chloride (NaCl) in 155 grams of water. If the molal boiling point constant for water (Kb) is 0.51 °C/m, what would be the boiling point of this solution? Show all of the work needed to solve this problem.
Answer:
106.6 °C
Step-by-step explanation:
The formula for boiling point elevation ΔTb is
ΔTb = iKb·b
where
i = the van't Hoff i# factor
Kb = the molal boiling point elevation constant
b = the molal concentration of the solution
=====
Data
i = 2, because 1 mol of NaCl gives 2 mol of ions in solution.
Kb = 0.51 °C·mol·kg⁻¹
b = 1.00/0.155
b = 6.452 mol·kg⁻¹
=====
Calculations
ΔTb = 2 × 0.51 × 6.452
ΔTb = 6.58°C
Tb = Tb° + ΔTb
Tb = 100 + 6.58
Tb = 106.6 °C
Carbon tetrachloride has been widely used in the cleaning industry, in fire extinguishers, and as a refrigerant. Construct an explanation of how carbon and chlorine combine to form carbon tetrachloride. A) Nonmetal carbon shares valence electrons with each nonmetal chlorine forming four covalent bonds. B) Nonmetal carbon loses a valence electron and chlorine metal gains a valence electron to form an ionic bond. C) Carbon and chlorine are nonmetals and they shares their valence electrons to become ions and form ionic bonds. D) Chlorine metal loses a valence electron to become a cation and nonmetal carbon gains a valence electron to become an anion forming a covalent bond.
Answer: A) Nonmetal carbon shares valence electrons with each nonmetal chlorine forming four covalent bonds.
Explanation: Covalent bond is formed by sharing of electrons between atoms.
Ionic bond is formed by transfer of electrons between atoms.
Carbon with atomic no 6 and has configuration of [tex]1s^22s^22p^2[/tex]. Carbon has 4 valence electrons. It can only share electrons as it is difficult to gain or lose 4 electrons to complete it's octet.
Chlorine with atomic no 17 has configuration of [tex]1s^22s^22p^3s^23p^5[/tex]. It has 7 valence electrons and need one electron to complete its octet.
Thus carbon will share 4 electrons, one each with four chlorine atoms to form carbon tetra chloride.
Answer:
A
Explanation:
Four galaxies are gravitationally bound, with each maintaining its own shape. What is this structure called?
D.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
A galaxy cluster.Explanation:
A galaxy cluster is a structure consisting in many galaxies bounded by gravitational forces maintaining their form, many clusters form superclusters galaxies. One of the notable clusters is Virgo cluster on the constellation of Virgo.
What molecular level property allows copper to be an ideal material to be used in electrical wiring? A) The solubility of copper and copper compounds. B) The freedom of electrons in the metallic bonding. C) Attractive forces within the copper alloyed wire. D) A high degree of crystallinity in the bulk structure.
B. the freedom of electrons in the metallic bonding
Answer: Option (B) is the correct answer.
Explanation:
Copper is known as the best conductor of heat and electricity. This is because in copper there is availability of free electrons.
And, as it is known that electricity is the flow of electrons. This means that since copper metal contains a number of free electrons. Hence, it can easily conduct electricity.
Electronic configuration of copper is [tex][Ar]4s1 3d^{10}[/tex]
Thus, we can conclude that freedom of electrons in the metallic bonding at molecular level property allows copper to be an ideal material to be used in electrical wiring.
According to Newton's First Law of Motion, what does it take to move an object at rest?
A.a force greater than the force keeping the object at rest
B.a force equal to the force keeping the object at rest, but in the opposite direction
C.a frictionless surface and a net force of 100N
D.the force of inertia cannot be overcome without changing gravity
It will be B.) A force equal to the force keeping the object at rest, but in the opposite direction.
Methanol (CH3OH) has a boiling point of -97°C. Methane (CH4) has a boiling point of -162°C. Which type of bonding explains why methanol has a much higher boiling point than methane?
Answer is: hydrogen bonding.
Methanol has stronger intermolecular bonds than methane.
Intermolecular forces are the forces between molecules or particles.
There are several types of intermolecular forces: hydrogen bonding, ion-induced dipole forces, ion-dipole forces andvan der Waals forces.
Hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom (H), covalently bound to a highly electronegative atom such as flourine (F), oxygen (O) and nitrogen (N) atoms.
Which metal will form a compound with the general formula m2co3 when it combines with a carbonate ion
the answer is Lithium.
The question is incomplete, here is the complete question.
Which metal will form a compound with the general formula [tex]M_2CO_3[/tex] when it combines with a carbonate ion
A. Beryllium
B. Aluminum
C. Calcium
D. Lithium
Answer: The metal that will form the given compound is lithium.
Explanation:
We are given:
A general chemical formula of carbonate, which is [tex]M_2CO_3[/tex]
The given compound is an ionic compound.
Carbonate is a polyatomic ion having chemical formula [tex]CO_3^{2-}[/tex]
Metal ion has a charge of +1.
For the given options:
Option A: Beryllium is the 4th element of the periodic table having electronic configuration of [tex]1s^22s^2[/tex]
This element will loose 2 electrons to form [tex]Be^{2+}[/tex] ion.
Option B: Aluminium is the 13th element of the periodic table having electronic configuration of [tex]1s^22s^22p^63s^23p^1[/tex]
This element will loose 3 electrons to form [tex]Al^{3+}[/tex] ion.
Option C: Calcium is the 20th element of the periodic table having electronic configuration of [tex]1s^22s^22p^63s^23p^64s^2[/tex]
This element will loose 2 electrons to form [tex]Ca^{2+}[/tex] ion.
Option D: Lithium is the 3rd element of the periodic table having electronic configuration of [tex]1s^22s^1[/tex]
This element will loose 1 electron to form [tex]Li^{+}[/tex] ion.
Hence, the metal that will form the given compound is lithium.
What volume of a 9.00 M NaOH stock solution would you need to make 800. ML of a 0.750 M NaOH solution
Answer: 66.66 ml
Explanation: Using Molarity equation:
[tex]M_1V_1[/tex] (stock solution)=[tex]M_2V_2[/tex](solution to be prepared)
given: [tex]M_2=0.750M[/tex]
[tex]V_2=800ml[/tex]
[tex]M_1=9.00M[/tex]
[tex]V_1=?[/tex]
[tex]9.00M\times V_1[/tex] (stock solution)=[tex]0.750M\times 800ml[/tex] (solution)
[tex]V_1= 66.66ml[/tex]
Which of the following statements is true about isotopes of the same element? Click on all that apply (1 point)
Isotopes have the same number of protons
Isotopes have the same number of electrons
Isotopes have the same number of neutrons
Isotopes have the same atomic mass
Isotopes have the same atomic number
Isotopes of the same element have identical numbers of protons and electrons (in a neutral state), and thus they share the same atomic number. They differ in the number of neutrons they possess, which leads to different atomic masses.
The question concerns isotopes of the same element. Two key characteristics of isotopes are their atomic number, which remains constant because isotopes have the same number of protons, and their varied atomic mass due to a different number of neutrons.
Isotopes have the same number of protons.
Isotopes have the same number of electrons (if the atom is in a neutral state).
Isotopes have the same atomic number.
Statements about isotopes having the same number of neutrons or the same atomic mass are incorrect; these are the properties that distinguish one isotope of an element from another.
The true statements are:
a) Isotopes have the same number of protons.
b) Isotopes have the same number of electrons.
e) Isotopes have the same atomic number.
Isotopes are variations of the same element that have the same number of protons, but different numbers of neutrons. This means they have different mass numbers, which is the sum of protons and neutrons in the nucleus. Here are the true statements about isotopes of the same element:
Isotopes have the same number of protons: The number of protons (atomic number) defines the element. All isotopes of an element have this same atomic number.
Isotopes have the same number of electrons: In a neutral atom, the number of electrons is equal to the number of protons. Therefore, isotopes of the same element have the same number of electrons.
Isotopes have the same atomic number: Because the atomic number is defined by the number of protons, which is consistent across isotopes of an element, the atomic number remains the same.
explain how atoms(ions) are held together in an ionic bond. Give an example of an ionic compound
Ionic bond is described as the chemical bond between two oppositely charged ions. In ionic bond the metal loses electron forming a positively charged cation and a non metal which accept the cation to form a negatively charged anion. In ionic bond the atoms are held together by electrostatic force of attraction. In ionic bond the anions and cations are present in the ratio where the total charge of the compound becomes zero. For example, Let us consider NaCl compound. An atom of the sodium has three electrons in its valency shell and the electrons are removed from the outer most shell by applying the energy of 5.14 electron volts. The chlorine atom lacks an electron to attain stable electronic configuration and it accepts the electron from the sodium by releasing 3.62 electron volts of energy which means that it takes only 1.52 electron volts of energy to donate an electron to chlorine when both the atoms are far apart. When these electrons are brought together their electric potential becomes more negative. This means that if the neutral sodium and chlorine atoms are found themselves closer it would be energetically favourable to transfer electrons from sodium to chlorine thus resulting in the formation of the ionic bond.
The ions in an ionic bond are held together by electrostatic attraction between the anions and cations in the compound.
For example, sodium chloride [NaCl] (more commonly known as salt) has positively charged sodium [Na+] ions, or cations, and negatively charged chlorine [Cl-] ions, or anions, holding the compound together.
According to Newton's First Law of Motion, what does it take to move an object at rest?
A.a force greater than the force keeping the object at rest
B.a force equal to the force keeping the object at rest, but in the opposite direction
C.a frictionless surface and a net force of 100N
D.the force of inertia cannot be overcome without changing gravity