Answer:
The full amount (5.00 g) will be dissolved in 1 L of water at 25°C.
Explanation:
The molecular weight (MW) of Vanillin (C₈H₈O₃) is calculated from the chemical formula as follows:
MW(C₈H₈O₃) = (12 g/mol x 8) + (1 g/mol x 8) + (16 g/mol x 3) = 152 g/mol
If 0.070 mol of C₈H₈O₃ are soluble per liter of water at 25°C, the maximum mass that can be dissolved in 1 L is:
0.070 mol x 152 g/mol = 10.64 g
Since 5.00 g is lesser than the maximum amount that can be dissolved (10.64 g), the added amount will be completely dissolved in 1 L of water at 25°C.
How many oxygen atoms are there in 0.25 mole of CO2?
Answer:
It is known that 1 mol of a molecule contains 6.023×1023 6.023 × 10 23 number of molecules. So, 0.25 moles of CO2 C O 2.
The correct option for the given question about Mole Concept is Na / 2 atom of oxygen.
What is mole?In chemistry, a mole is a unit. A mole of a substance is the mass of the substance containing precisely 12 gram of the same number of atoms as 12C.The mole is the SI unit used to measure a substance's quantity. It has the symbol mol.
How to solve this question?
In 1 mole number of molecules of CO₂ = Na (Avagadro Number)
In 0.25 mole number of molecules of CO₂ = 0.25 × Na molecules
In 1 molecule number of oxygen atom = 2 atom
In 0.25 × Na molecules number of oxygen atom = 2 × 0.25 × Na atom
In 0.25 × Na molecules number of oxygen atom = 0.5 × Na atom
So in 0.25 mole of CO₂ number of oxygen atom = Na / 2 atom
Thus we can conclude that in 0.25 mole of CO₂ number of oxygen atom will be Na / 2, where Na is Avagadro Number.
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tom pays 5 cents per minute to use his cell phone. Write an expression for the cost in cents of using his cell phone for minutes.
Answer:5m
Explanation:Because in the question it say per minute so it would be 5 times m
For which of the following reactions is the enthalpy change equal to the second ionization energy of nitrogen?
Answer:
"[tex]N^+(g) \rightarrow N^{2+}(g) + e^-[/tex]" is the appropriate answer.
Explanation:
Whenever one electron or particle must be removed from some kind of gas atom or molecule, it requires that the very first amount of energy necessary.Two electrons must be removed from such a mono-positive exhaust gases structure or position of ion before they may become a dipositive gaseous ion.Thus the above is the correct answer.
What 2 variables are needed to calculate the percent yield?
Answer:
isn’t it reactants and products?
Explanation:
Answer: reactants and products
Explanation:
tính chất hóa học của propylen
Answer:
Propilen là một chất khí không màu với mùi giống như dầu mỏ. Propilen nhẹ hơn nước và tan rất ít trong nước 0.61 g/ . Không hòa tan trong các dung môi phân cực như nước, chỉ tan trong dung môi không phân cực hay ít phân cực.. Propilen không có tính dẫn điện.
What do we need to know to understand the formation of a chemical bond?
Answer:
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds.
Explanation:
You have to put energy into a molecule to break its chemical bonds. The amount needed is called the bond energy. After all, molecules don't spontaneously break
At 445oC, Kc for the following reaction is 0.020. 2 HI(g) <--> H2 (g) + I2 (g) A mixture of H2, I2, and HI in a vessel at 445oC has the following concentrations: [HI] = 1.5 M, [H2] = 2.50 M and [I2] = 0.05 M. Which one of the following statements concerning the reaction quotient, Qc, is TRUE for the above system?
a. Qc = Kc; the system is at equilibrium.
b. Qc is less than Kc; more H2 and I2 will be produced.
c. Qc is less than Kc; more HI will be produced.
d. Qc is greater than Kc; more HI will be produced.
Explanation:
The given balanced chemical equation is:
[tex]2 HI(g) <--> H_2 (g) + I_2 (g)[/tex]
The value of Kc at 445oC is 0.020.
[HI]=1.5M
[H2]=2.50M
[I2]=0.05M
The value of Qc(reaction quotient ) is calculated as shown below:
Qc has the same expression as the equilibrium constant.
[tex]Qc=\frac{[H_2][I_2]}{[HI]^2} \\Qc=(2.50Mx0.05M)/(1.5M)^2\\Qc=0.055[/tex]
Qc>Kc,
Hence, the backward reaction is favored and the formation of Hi is favored.
Among the given options, the correct answer is option d. Qc is greater than Kc; more HI will be produced.
4. A sample of ammonia, NH3, contains 3.3 x 1021 hydrogen atoms. How many NH; molecules are in this sample?
Answer:
1.1 × 10²¹ NH₃ molecules
Explanation:
From the given information:
We were being told that the number of the hydrogen (H) atoms present in the sample of NH3 = 3.3 × 10²¹ hydrogen.
However, it signifies that each molecule of ammonia harbors 3hydrogen (H) atoms.
Hence, the number of molecules of NH₃ present;
[tex]\mathsf{=\dfrac{3.3\times 10^{21}}{3} \ molecules \ of \ {NH_3}}[/tex]
= 1.1 × 10²¹ NH₃ molecules
HELP ASAS 15 POINTS
When using the process of evaporation to separate a mixture, what is left behind in the evaporating dish?
A. None of these.
B. The liquid evaporates and the solid is left in the dish.
C. The mixture does not separate, and the entire mixture evaporates.
D. The mixture does not separate, and the entire mixture remains in the dish.
Answer:
liquid will be evaporated while solid remains
Which option is a physical property of matter?
A. acidity
B. reactivity
C. boiling point
D. flammability
Answer:
boiling point is the physial property of matter
The option that is showing the physical property of the matter is boiling point, the correct option is C.
What is physical property?A physical property is any measurable property whose value describes the state of a physical system.
Changes in a system's physical properties can be used to describe its transitions between momentary states. Physical properties are also known as observables. They do not have modal properties.
Physical properties include color, phase, odor, and boiling point. Since reactivity with oxygen is dependent on the chemical nature of the object, it is not a physical property.
A compound's physical property is one that can be observed and measured. The chemical composition of a compound is unaffected by a physical property.
Thus, the correct option is C.
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A(n) _____, used as part of the stationary phase, has an affinity for the solvent and the chemical components of the mixture. adsorbent eluent Rf factor chromatogram
The Adsorbent is used as part of the stationary phase and has an affinity for the solvent and the chemical components of the mixture.
The adsorbent has a high affinity for solvent and the chemical components of the mixture.
Chromatography is a method of separation in which the mixture of substances is introduced into a mobile phase (solvent). The separation occurs as the solvent interacts with an adsorbent(stationary phase).
The extent of separation of the components of the mixture depends on the extent of interaction between the mobile and the stationary phase . This interaction also determines the retention factor (Rf) of the separation.
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Oxygen and hydrogen are compressed into two cubical boxes of the same
size at a temperature of 28 K. What do these gases have in common
according to the kinetic theory?
Explanation:
Following are the kinetic theory of gases postulates:
1) Space-volume to molecules ratio is negligible.
2)There is no force of attraction between the molecules at normal temperature and pressure. The force of attraction between the molecules build when the temperature decreases and the pressure increases.
3) There is large space between the molecules resulting in continuous motion.
4) The free movement of molecules results in collision which is perfectly elastic.
5) The molecules have kinetic energy due to random movement. But the average kinetic energy of these molecules differs with temperature.
6) Molecules exert pressure on the walls of the container.
Net ionic reaction of H2SO4 with Ba(OH)2
Answer:
This is an acid-base reaction (neutralization): Ba(OH) 2 is a base, H 2SO 4 is an acid. This is a precipitation reaction: BaSO 4 is the formed precipitate.
According to the ideal gas law, a 9.998 mol sample of argon gas in a 0.8311 L container at 502.7 K should exert a pressure of 496.2
atm. What is the percent difference between the pressure calculated using the van der Waals' equation and the ideal pressure? For Ar
gas, a = 1.345 L’atm/mol? and b = 3.219x10-2 L/mol.
Pideal – Puan der Waals |
Percent difference
x 100
Answer:
[tex]\%diff=24.0\%[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary for us to set up the van der Waals' equation as shown below:
[tex]p=\frac{RT}{v-b}-\frac{a}{v^2}[/tex]
Thus, we secondly calculate the molar volume as:
[tex]v=\frac{0.8311L}{9.998mol} =0.083L/mol[/tex]
Then, we plug in the entire variables in the vdW equation to get such pressure:
[tex]p=\frac{0.08206\frac{atm*L}{mol*K}*502.7K}{0.08313L/mol-0.03219L/mol}-\frac{1.345L*atm/mol}{(0.08313L/mol)^2}\\\\p=615.2atm[/tex]
And the ideal gas pressure:
[tex]p=\frac{0.08206\frac{atm*L}{mol*K}*502.7K}{0.08313L/mol}\\\\p=496.2atm[/tex]
Finally, the percent difference:
[tex]\%diff=\frac{|496.2atm-615.2atm|}{496.2atm} *100\%\\\\\%diff=24.0\%[/tex]
Regards!
Match each land resource to its use.
clay - used to make steel
iron ore - used to make batteries
salt - used to make pottery and tiles
aggregate - used in construction
graphite - used as a flavoring in food
i will give 10 points and brainliest!!!
Answer:
Explanation:
We are to match each land resource to what they are being used for.
Clay →→→ used to make pottery and tiles
iron ore →→→ used to make steel
Salt →→→ used as a flavoring in food
aggregate →→→ used in construction
graphite →→→ used to make batteries
Clay is a kind of soil particle that forms as a result of weathering processes. Examples include; pottery clays, glacial clays, and deep-sea clays e.t.c. The presence of one or more clay minerals, as well as variable quantities of organic and detrital components, characterizes all of them. Clay is usually sticky and moist when wet, but hard when dry. They are used in the making of tiles and potteries.
Iron ore: The iron ore deposits are found in the Earth's crust's sedimentary rocks. They're made up of iron and oxygen that mix during the chemical process in marine and freshwater. iron ores are used to produce almost every iron and steel product that we use today.
Aggregate: are utilized in construction activities. It is a material used to mix cement, gypsum, bitumen, or lime to produce concrete in the construction industry.
Graphite: Graphite is a mineral that occurs in both igneous and metamorphic rocks. It is generally generated on the earth's surface when carbon is exposed to high temperatures and pressures. It is mainly used in the production of batteries and electrodes,
Atoms that have a positive or negative electrical charge are called ________.
Explanation:
They are called or known as cations
Consider the constitutional isomers 2-methylbut-1-ene, 2-methylbut-2-ene, and 3-methylbut-1-ene. When each of these alkenes is subjected to catalytic hydrogenation (H2, Pt), a single product results. Which of the following best describes the structural relationship among these products?
a. the product are cis-trans isomers.
b. the product are identical.
c. the product are constitutional isomers.
d. the product are enantiomers.
e. the product are diastereomers.
Answer:
Explanation:
I am almost sure that the products are identical.
Why is it difficult to classify dissolving as simply a physical or a chemical change? (1 point)
O Some substances keep the same molecular structure when they break down, and others do not.
O Some substances release energy when they dissolve, and some absorb energy.
O Some substances taste the same after they dissolve, and others do not.
O Some substances keep the same color when they dissolve, and others do not.
Answer:
It is difficult because of C
Explanation:
The correct answer is:Some substances keep the same molecular structure when they break down, and others do not.
Some substances change their form when they dissolve and some do not. Dissolution can sometimes be regarded as a sort of reaction between a chemical substance and water.
Usually, we can consider dissolution of a substance in water as a sort of chemical reaction for some substances. For instance, an ionic substance interacts with water to form ions. similarly, some salts become hydrolysed in water and give acidic/basic solutions as result of that.
However, some substances do not interact with water upon dissolution. They rather remain as molecular entities because they are not composed of ions.
We can see that some substances keep the same molecular structure when they break down, and others do not keep the same molecular structure when they dissolve hence it is difficult to classify dissolving as a physical or a chemical change.
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1. Explain the test for unsaturation.
2. Write down the balanced chemical equations for the complete and incomplete
combustion of octene
3. Explain how propanol, an alcohol, is formed from propene..
4. How is margarine formed?
Answer:
1)In organic chemistry, the bromine test is a qualitative test for the presence of unsaturation (carbon-to-carbon double or triple bonds), phenols and anilines. ... The more unsaturated an unknown is, the more bromine it reacts with, and the less coloured the solution will appear.
2)The equation for incomplete combustion of propane is: 2 C3H8 + 9 O2 → 4 CO2 + 2 CO + 8 H2O + Heat. If not enough oxygen is present for complete combustion, incomplete combustion occurs. The result of incomplete combustion is, once again, water vapour, carbon dioxide and heat. But it also produces carbon monoxide.
Explanation:
3)Propene, also known as propylene, is an unsaturated organic compound with the chemical formula {\displaystyle {\ce {CH3CH=CH2}}}. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petroleum-like odor.
Formula: C3H6
IUPAC ID: Propene
4)Margarines are chemically created during hydrogenation which, until January 1, 2006, relied upon trans fats to solidify their vegetable oils. Food companies have been exploring options for replacing trans fat in partially hydrogenated margarine.
PLEASE HELP! A machine uses filtration to separate a component from orange juice. Which component does the machine most likely separate from the mixture?
A - Pigment
B - Sugar
C - Pulp
D - Water
Answer: c
Explanation: Filtration is technically defined as the process of separating suspended solid matter from a liquid
Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops .
Many commercial juices are filtered to remove fiber or pulp.
The correct answer is C, Pulp.
Orange is an example of a citrus fruit. Every citrus fruit has a pulp. The of pulp a citrus fruit is that stringy content in the endocarp of the fruit .
The pulp of a citrus fruit is where its juice is found.
When you want to prepare orange juice, you need to remove the pulp of the citrus fruit. This is done by filtering out the pulp from the juice.
Filtration is the process of removing larger particles. For a liquid juice, filtration is the process of removing solid particles from the orange juice.
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If you have a polyatomic anion of Ammonium (NH41+), how many valence electrons must your Lewis Structure have?
Answer:
One can draw the 3-dimensional structure of an atom once they have the Lewis Structure of an atom. The 3-dimensional geometrical structure of ammonium, NH4+ is referred to as Tetrahedral. ... But the + sign decrees that NH4+ has 8 valence shell electrons, due to the positive ion.
Explanation:
Which are the following exothermic or endothermic
Absorbs Energy
-Hrxn
+Hrxn
Feels Hot
Heat flows from surrounds to Reaction
Not Energetically Favorable
Energetically Favorable
Releases Energy
Feels Cold
Heat flows from the reaction to the surrounds
Answer:
Explanation:
Your mom
Five kg of carbon dioxide (CO2) gas undergoes a process in a well-insulated piston-cylinder assembly from 2 bar, 280 K to 20 bar, 520 K. If the carbon dioxide behaves as an ideal gas, determine the amount of entropy produced, in kJ/K.
This question is incomplete, the complete question is;
Five kg of carbon dioxide (CO2) gas undergoes a process in a well-insulated piston-cylinder assembly from 2 bar, 280 K to 20 bar, 520 K. If the carbon dioxide behaves as an ideal gas, determine the amount of entropy produced, in kJ/K. Assuming;
a) constant specific heats Cp = 0.939 kJ/Kg K
b) variable specific heats
Answer:
a) the amount of entropy produced is 0.731599 kJ/K
b) the amount of entropy produced is 0.69845 kJ/K
Explanation:
Given the data in the question;
5 kg of carbon dioxide (CO₂) gas undergoes a process in a well-insulated piston-cylinder assembly.
m = 5 kg
Molar mass M = 44.01 g/mol
P₁ = 2 bar, P₂ = 20
T₁ = 280 K, P₂ = 520 K
Since its insulated { q = 0 } ( kinetic and potential energy effects = 0 )
Now,
a) the amount of entropy produced, in kJ/K, Assuming constant specific heats with Cp = 0.939 kJ/Kg K
S[tex]_{Generation[/tex] = m × ((Cp × In( T₂/T₁) - R × In( P₂/p₁ ))
we substitute
S[tex]_{Generation[/tex] = 5 × (( 0.939 × In( 520/280) - 0.1889 × In( 20/2 ))
= 5 × ( 0.5812778 - 0.434958 )
= 5 × 0.1463198
= 0.731599 kJ/K
Therefore, the amount of entropy produced is 0.731599 kJ/K
b) the amount of entropy produced, in kJ/K, Assuming variable specific heats.
Now, from Table A-23: Ideal Gas Properties of Selected Gases;
T₁,T₂ : s₁⁰ = 211.376 kJ/kmol-K, s₂⁰ = 236.575 kJ/kmol-K
now, s₁ = s₁⁰ / M and s₂ = s₂⁰ / M
we substitute
s₁ = s₁⁰ / M = 211.376 / 44.01 = 4.8029 kJ/kg
s₂ = s₂⁰ / M = 236.575 / 44.01 = 5.37548 kJ/kg
S[tex]_{Generation[/tex] = m × (( s₂ - s₁ ) - R × In( p₂ / p₁ ))
we substitute
S[tex]_{Generation[/tex] = 5 × (( 5.37548 - 4.8029 ) - 0.1880 × In( 20 / 2 ))
= 5 × ( 0.57258 - 0.432885997 )
= 5 × 0.13969
= 0.69845 kJ/K
Therefore, the amount of entropy produced is 0.69845 kJ/K
Using the molarity of vinegar, calculate the mass percent of acetic acid in the original sample. Assume the density of vinegar is 1.00 g/mL. (The formula for acetic acid is C2H4O2).
Answer:
5.37% w/w is the mass percent of vinegar assuming a molarity of 0.8935mol/L
Explanation:
Assuming the molarity of vinegar is 0.8935mol/L:
Mass percent is defined as 100 times the ratio between mass of solute (In this case, acetic acid), and the mass of the solution
To solve this question we need to find the mass of acetic acid from the moles using the molar mass and the mass of the solution from the volume in liters using the density:
Mass Acetic acid -Molar mass: 60.052g/mol-
0.8935mol * (60.052g / mol) = 53.656g Acetic Acid
Mass Solution:
1L = 1000mL * (1.00g/mL) = 1000g Solution
Mass Percent:
53.656g Acetic Acid / 1000g Solution * 100 =
5.37% w/w is the mass percent of vinegar assuming a molarity of 0.8935mol/LThe mass percent of acetic acid in the original sample of vinegar of molarity 0.8935mol/L is 5.37% w/w.
How do we calculate the mass percent?Mass percent of any solute present in any solution will be calculated as the:
Mass % of solute = (mass of solute / mass of solution) × 100
Let the molarity of vinegar = 0.8935mol/L
Means 0.8935 moles of vinegar present in the 1 liter of the solution.
Now we calculate mass from moles as:
n = W/M, where
W = required mass
M = molar mass = 60.052g /mol
W = (0.8935mol)(60.052g/mol) = 53.656g
Mass of solution = 1L = 1000mL×(1.00g/mL) = 1000g Solution
Then the mass % of acetic acid:
Mass % = (53.656g / 1000g) × 100 = 5.37% w/w
Hence the required % mass is 5.37% w/w.
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Write the complete ground-state electron configuration of I⁻.
Explanation:
here's the answer to your question
Iodine's neutral atom has the following electronic configuration: 1 s² 2 s² 2 p⁶ 3 s² 3 p⁶ 4 s² 3 d¹⁰ 4 p⁶ 5 s² 4 d¹⁰ 5 p⁵. The complete ground-state electron configuration of I⁻ is [Kr]5s² 4d¹⁰ 5p⁶.
What is electronic configuration?Electronic configuration is defined as each electron moves individually within an orbital while being surrounded by an average field produced by all other orbitals. The electron configuration is used to describe an atom's ground state orbitals, but it may also be used to depict an atom that has ionized into a cation or anion by making up for any lost or gained electrons in the orbitals after it.
The ground state electronic configuration is defined as the configuration of lower energy electrons surrounding an atom's nucleus. Ground state is defined as the least energetic state feasible for a physical system. It is important because permits us to determine the location of the excited electrons' departure and return when they release a photon.
Thus, iodine's neutral atom has the following electronic configuration: 1 s² 2 s² 2 p⁶ 3 s² 3 p⁶ 4 s² 3 d¹⁰ 4 p⁶ 5 s² 4 d¹⁰ 5 p⁵. The complete ground-state electron configuration of I⁻ is [Kr]5s² 4d¹⁰ 5p⁶.
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The density of an aqueous solution containing 25.0 percent of ethanol (C2H5OH) by mass is 0.950 g/mL. (a) Calculate the molality of this solution. m (b) Calculate its molarity. M (c) What volume of the solution would contain 0.275 mole of ethanol
Answer:
a. 7.24m
b. 5.15M
c. 53.4mL of the solution would contain this amount of ethanol.
Explanation:
Molality, m, is defined as the moles of solute (ethanol, in this case) per kg of solvent.
Molarity, M, are the moles of solute per kg of solvent
To solve this question we need to find the moles of solute in 100g of solution and the volume using its density as follows:
a. Moles ethanol -Molar mass: 46.07g/mol-:
25g ethanol * (1mol/46.07g) = 0.54265 moles ethanol
kg solvent:
100g solution - 25g solute = 75g solvent * (1kg / 1000g) = 0.075kg
Molality:
0.54265 moles ethanol / 0.075kg = 7.24m
b. Liters solution:
100g solution * (1mL / 0.950g) = 105.3mL * (1L / 1000mL) = 0.1053L
Molarity:
0.54265 moles ethanol / 0.1053L = 5.15M
c. 0.275 moles ethanol * (1L / 5.15moles Ethanol) = 0.0534L =
53.4mL of the solution would contain this amount of ethanol
I NEED A ANSWER FOR THIS QUESTION, ASAP
If the Ksp of NaCl is experimentally determined to be 43.9, then what is the concentration of Na (in M) when it begins to crystallize out of solution
Answer:
6.63 M
Explanation:
NaCl(s) ---> Na^+(aq) + Cl^-(aq)
Given that [Na^+] = [Cl^-] = s
Where s= concentration of the both ions
Ksp = s^2
s= √Ksp
s= √43.9
s= 6.63 M
The concentration of Na (in M) obtained when it begins to crystallize out of solution is 6.63 M
What is solubility of product?The solubility of product (Ksp) is defined as the concentration of products raised to their coefficient coefficients. This is illustrated below:
mX <=> nY + eZ
Ksp = [Y]^n × [Z]^e
Dissociation equationNaCl(aq) → Na⁺(aq) + Cl¯(aq)
Let the concentration of Na⁺ be yLet the concentration of Cl¯ be yHow to determine the concentration of Na⁺ Solubility of product (Ksp) = 43.9Concentration of Cl¯ = yConcentration of Na⁺ = y =?Ksp = [Na⁺] × [Cl¯]
43.9 = y × y
43.9 = y²
Take the square root of both side
y = √43.9
y = 6.63 M
Thus, the concentration of Na⁺ is 6.63 M
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Isotopes are: A. are only theoretical. B. only formed in laboratories. C. found in nature. D. found in the nuclear reactions in stars but not on Earth.
Answer:
B. only formed in laboratories
Explanation:
i know
Isotopes are only formed in Laboratories. hence, Option (B) is correct.
What are Isotopes ?
Each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element is known as Isotope.
Isotopes are two or more types of atoms that have the same atomic number and position in the periodic table, and that differ in nucleon numbers due to different numbers of neutrons in their nuclei.
Therefore, Isotopes are only formed in Laboratories. hence, Option (B) is correct.
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The shape of a molecule is determined by:
A. All of these
B. The number of electron clouds around the atom.
C. The number of bonds.
D. Mutual repulsion between electrons.
