Question 1

Why is CaO the symbol for calcium oxide instead of CAO?

Accepted Answer

A) both can be the symbols for calcium oxide 
B) both are incorrect; the symbol is cao 
C) a capital letter means a new symbol 
D) both are incorrect as the symbol should be CaOx 
A) both can be the symbols for calcium oxide 
B) both are incorrect; the symbol is cao 
C) a capital letter means a new symbol 
D) both are incorrect as the symbol should be CaOx

Question 2

Which of the following has the largest mass?

Accepted Answer

A) 5.0 mol H2O 
B) 3.5 mol NH3 
C) 8.0 mol C 
D) 6.0 mol C2H2 
A) 5.0 mol H2O 
B) 3.5 mol NH3 
C) 8.0 mol C 
D) 6.0 mol C2H2

Question 3

How many protons are found in the nucleus of a boron-11 (11B)atom?

Accepted Answer

A) 11 
B) 6 
C) 5 
D) 4 
A) 11 
B) 6 
C) 5 
D) 4

Question 4

Isotopes of the same element always have the same atomic mass.

Accepted Answer

A) True 
 B)False

Question 5

The first letter of the symbol for each of the elements is the first letter of its English name.

Accepted Answer

A) True 
 B)False

Question 6

Which element is approximately 65 percent of sulfuric acid by weight?

Accepted Answer

A) hydrogen 
B) sulfur 
C) oxygen 
D) any of these 
A) hydrogen 
B) sulfur 
C) oxygen 
D) any of these

Question 7

Consider the representation shown below.  It should be classified as

Accepted Answer

A) an element consisting of 6 atoms. 
B) a compound containing atoms of two elements. 
C) a homogenous mixture of two elements. 
D) a homogenous mixture of two compounds. 
A) an element consisting of 6 atoms. 
B) a compound containing atoms of two elements. 
C) a homogenous mixture of two elements. 
D) a homogenous mixture of two compounds.

Question 8

In naturally occurring samples, all elements exist as a mixture of isotopes.

Accepted Answer

A) True 
 B)False

Question 9

Which of the following is located in the nucleus of an atom?

Accepted Answer

A) protons 
B) neutrons 
C) electrons 
D) protons and neutrons 
A) protons 
B) neutrons 
C) electrons 
D) protons and neutrons

Question 10

Using whole numbers, determine the molecular weight of calcium hydroxide, Ca(OH)2.

Accepted Answer

A) 56 
B) 57 
C) 58 
D) 74 
A) 56 
B) 57 
C) 58 
D) 74

Question 11

How many atoms are contained in a sample of krypton, Kr, that weighs 8.38 g?

Accepted Answer

A) one Avogadro's number 
B) one-tenth Avogadro's number 
C) one 
D) one-tenth 
A) one Avogadro's number 
B) one-tenth Avogadro's number 
C) one 
D) one-tenth

Question 12

How many moles of Na2Cr2O7 contain 14 moles of oxygen atoms?

Accepted Answer

A) 2 mol Na2Cr2O7 
B) 14 mol Na2Cr2O7 
C) 7 mol Na2Cr2O7 
D) 1 mol Na2Cr2O7 
A) 2 mol Na2Cr2O7 
B) 14 mol Na2Cr2O7 
C) 7 mol Na2Cr2O7 
D) 1 mol Na2Cr2O7

Question 13

What is the number of moles of water in one liter of water if one gram of water takes up one milliliter of space?

Accepted Answer

A) 1 
B) 18 
C) 55.6 
D) 1000 
A) 1 
B) 18 
C) 55.6 
D) 1000

Question 14

One mole of silver would contain the same number of atoms as a mole of gold.

Accepted Answer

A) True 
 B)False

Question 15

Calculate the weight percentage of hydrogen in water.

Accepted Answer

A) 33.3 
B) 66.7 
C) 2.00 
D) 11.1 
A) 33.3 
B) 66.7 
C) 2.00 
D) 11.1

Question 16

How many moles of oxygen atoms are in one mole of CO2?

Accepted Answer

A) 1 
B) 2 
C) 6.02 × 1023 
D) 12.04 × 1023 
A) 1 
B) 2 
C) 6.02 × 1023 
D) 12.04 × 1023

Question 17

Naturally occurring neon (Ne)has the following isotopic composition (the mass of each isotope is given in parenthesis). Calculate the atomic weight of neon in u from these data:  neon-20, 90.92% (19.99 u); neon-21, 0.257% (20.99 u); neon-22, 8.82% (21.99 u)

Accepted Answer

A) 28.97 
B) 37.62 
C) 2017 
D) 20.17 
A) 28.97 
B) 37.62 
C) 2017 
D) 20.17

Question 18

Neutral isotopes of the same element have the same number of electrons.

Accepted Answer

A) True 
 B)False

Question 19

A neutral isotope of an element contains 21 electrons and 24 neutrons.  What is the following representation for this nucleus?

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 20

Oxalic acid is found in many plants, like spinach and black tea.  What is the mass of the carbon found in one mole of oxalic acid, H2C2O4?

Accepted Answer

A) 12.01 g of C 
B) 24.02 g of Cl 
C) 45.01 g of C 
D) 90.02 g of C 
A) 12.01 g of C 
B) 24.02 g of Cl 
C) 45.01 g of C 
D) 90.02 g of C

Exam 2: Atoms and Molecules

Why is CaO the symbol for calcium oxide instead of CAO?

Which of the following has the largest mass?

How many protons are found in the nucleus of a boron-11 (11B)atom?

Isotopes of the same element always have the same atomic mass.

The first letter of the symbol for each of the elements is the first letter of its English name.

Which element is approximately 65 percent of sulfuric acid by weight?

Consider the representation shown below. It should be classified as

In naturally occurring samples, all elements exist as a mixture of isotopes.

Which of the following is located in the nucleus of an atom?

Using whole numbers, determine the molecular weight of calcium hydroxide, Ca(OH)2.

How many atoms are contained in a sample of krypton, Kr, that weighs 8.38 g?

How many moles of Na2Cr2O7 contain 14 moles of oxygen atoms?

What is the number of moles of water in one liter of water if one gram of water takes up one milliliter of space?

One mole of silver would contain the same number of atoms as a mole of gold.

Calculate the weight percentage of hydrogen in water.

How many moles of oxygen atoms are in one mole of CO2?

Naturally occurring neon (Ne)has the following isotopic composition (the mass of each isotope is given in parenthesis). Calculate the atomic weight of neon in u from these data: neon-20, 90.92% (19.99 u); neon-21, 0.257% (20.99 u); neon-22, 8.82% (21.99 u)

Neutral isotopes of the same element have the same number of electrons.

A neutral isotope of an element contains 21 electrons and 24 neutrons. What is the following representation for this nucleus?

Oxalic acid is found in many plants, like spinach and black tea. What is the mass of the carbon found in one mole of oxalic acid, H2C2O4?

Matter, Measurements, and Calculations

Electronic Structure and the Periodic Law

Forces Between Particles

Chemical Reactions

The States of Matter

Solutions and Colloids

Reaction Rates and Equilibrium

Acids, Bases, and Salts

Radioactivity and Nuclear Processes

Organic Compounds: Alkanes

Unsaturated Hydrocarbons

Alcohols, Phenols, and Ethers

Aldehydes and Ketones

Carboxylic Acids and Esters

Amines and Amides

Carbohydrates

Lipids

Proteins

Enzymes

Nucleic Acids and Protein Synthesis

Nutrition and Energy for Life

Carbohydrate Metabolism

Lipid and Amino Acid Metabolism

Body Fluids

Filters

How many protons are found in the nucleus of a boron-11 (¹¹B)atom?

Using whole numbers, determine the molecular weight of calcium hydroxide, Ca(OH)₂.

How many moles of Na₂Cr₂O₇ contain 14 moles of oxygen atoms?

How many moles of oxygen atoms are in one mole of CO₂?

Oxalic acid is found in many plants, like spinach and black tea. What is the mass of the carbon found in one mole of oxalic acid, H₂C₂O₄?