Question 1

A 500.gram iron ore sample was determined to contain 242 grams of iron.What is the mass percent of iron in the ore?

Accepted Answer

A) 93.7 
B) 48.4 
C) 51.6 
D) 32.6 
E) none of the above 
A) 93.7 
B) 48.4 
C) 51.6 
D) 32.6 
E) none of the above

Question 2

What is the mass (in grams)of 3.03 × 1024 molecules of carbon dioxide molecules?

Accepted Answer

A) 221 
B) 0.114 
C) 1.33 
D) 44.01 
E) none of the above 
A) 221 
B) 0.114 
C) 1.33 
D) 44.01 
E) none of the above

Question 3

A 7.96 gram sample of silver reacts with oxygen to form 8.55 gram of the metal oxide.What is the formula of the oxide?

Accepted Answer

A) AgO 
B) AgO2 
C) Ag2O 
D) Ag3O 
E) none of the above 
A) AgO 
B) AgO2 
C) Ag2O 
D) Ag3O 
E) none of the above

Question 4

One mole of nitrogen gas contains (2)× (6.022 × 1023)nitrogen atoms.

Accepted Answer

A) True 
 B)False

Question 5

What is the mass percent of oxygen in sodium oxide?

Accepted Answer

A) 37.1 
B) 25.8 
C) 74.2 
D) 62.0 
E) none of the above 
A) 37.1 
B) 25.8 
C) 74.2 
D) 62.0 
E) none of the above

Question 6

How many moles of carbon are in 3.5 moles of calcium carbonate?

Accepted Answer

A) 10.5 
B) 3.5 
C) 7 
D) 100.09 
E) none of the above 
A) 10.5 
B) 3.5 
C) 7 
D) 100.09 
E) none of the above

Question 7

Mass is used as a method of counting atoms.

Accepted Answer

A) True 
 B)False

Question 8

What is the mass of   sulfur atoms?

Accepted Answer

A) 208 
B) 4.93 
C) 155 
D) 32.07 
E) none of the above 
A) 208 
B) 4.93 
C) 155 
D) 32.07 
E) none of the above

Question 9

What is the molecular formula of a compound given the molar mass of the compound is 30.04 gram and the empirical formula is NH?

Accepted Answer

A) NH 
B) N2H2 
C) N2H6 
D) N4H4 
E) none of the above 
A) NH 
B) N2H2 
C) N2H6 
D) N4H4 
E) none of the above

Question 10

Avogadro's Number is 6.022 × 1023.

Accepted Answer

A) True 
 B)False

Question 11

What is the mass (in grams)of 1.95 moles of water ?

Accepted Answer

A) 18.02 
B) 9.24 
C) 35.1 
D) 6.022 × 1023 
E) none of the above 
A) 18.02 
B) 9.24 
C) 35.1 
D) 6.022 × 1023 
E) none of the above

Question 12

How many molecules of nitrogen monoxide are in a 22.5 gram sample?

Accepted Answer

A) 5.86 × 1023 
B) 7.33 × 1023 
C) 4.51 × 1023 
D) 4.06 × 1023 
E) none of the above 
A) 5.86 × 1023 
B) 7.33 × 1023 
C) 4.51 × 1023 
D) 4.06 × 1023 
E) none of the above

Question 13

An empirical formula gives the specific number of each type of atom in a molecule.

Accepted Answer

A) True 
 B)False

Question 14

The mass of 2.0 moles of H2O is greater than the mass of 1.0 mole of CO2.

Accepted Answer

A) True 
 B)False

Question 15

One half of a mole of atoms would contain how many atoms?

Accepted Answer

A) 0.5 
B) 3.011 × 1023 
C) 6.022 × 1023 
D) 6.022 × 1011.5 
E) none of the above 
A) 0.5 
B) 3.011 × 1023 
C) 6.022 × 1023 
D) 6.022 × 1011.5 
E) none of the above

Question 16

A compound composed of only hydrogen and oxygen is 5.94% hydrogen by mass.The molar mass of this compound is 34.02 g/mol.What is the compound's molecular formula?

Accepted Answer

A) 34.02 
B) H2O2 
C) HO 
D) H6O 
E) none of the above 
A) 34.02 
B) H2O2 
C) HO 
D) H6O 
E) none of the above

Question 17

The chemical formula CH2O can be classified as:

Accepted Answer

A) molecular only. 
B) empirical only. 
C) empirical,possibly molecular. 
D) not enough information 
E) none of the above 
A) molecular only. 
B) empirical only. 
C) empirical,possibly molecular. 
D) not enough information 
E) none of the above

Question 18

Which of the following compounds has the highest mass percent of "O"?

Accepted Answer

A) MnO 
B) MnO2 
C) Mn2O3 
D) Mn3O2 
E) none of the above 
A) MnO 
B) MnO2 
C) Mn2O3 
D) Mn3O2 
E) none of the above

Question 19

The numerical value of the mole is defined as being equal to the number of atoms in exactly 12 grams of pure carbon-12.

Accepted Answer

A) True 
 B)False

Question 20

One mole of CO2 gas contains 1 mole of carbon atoms and 2 moles of oxygen atoms.

Accepted Answer

A) True 
 B)False

A 500.gram iron ore sample was determined to contain 242 grams of iron.What is the mass percent of iron in the ore?

What is the mass (in grams)of 3.03 × 10²⁴ molecules of carbon dioxide molecules?

A 7.96 gram sample of silver reacts with oxygen to form 8.55 gram of the metal oxide.What is the formula of the oxide?

One mole of nitrogen gas contains (2)× (6.022 × 10²³)nitrogen atoms.

What is the mass percent of oxygen in sodium oxide?

How many moles of carbon are in 3.5 moles of calcium carbonate?

Mass is used as a method of counting atoms.

What is the mass of sulfur atoms?

What is the molecular formula of a compound given the molar mass of the compound is 30.04 gram and the empirical formula is NH?

Avogadro's Number is 6.022 × 10²³.

What is the mass (in grams)of 1.95 moles of water ?

How many molecules of nitrogen monoxide are in a 22.5 gram sample?

An empirical formula gives the specific number of each type of atom in a molecule.

The mass of 2.0 moles of H₂O is greater than the mass of 1.0 mole of CO₂.

One half of a mole of atoms would contain how many atoms?

A compound composed of only hydrogen and oxygen is 5.94% hydrogen by mass.The molar mass of this compound is 34.02 g/mol.What is the compound's molecular formula?

The chemical formula CH₂O can be classified as:

Which of the following compounds has the highest mass percent of "O"?

The numerical value of the mole is defined as being equal to the number of atoms in exactly 12 grams of pure carbon-12.

One mole of CO₂ gas contains 1 mole of carbon atoms and 2 moles of oxygen atoms.

The Chemical World

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Matter and Energy

Atoms and Elements

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Chemical Reactions

Quantities in Chemical Reactions

Electrons in Atoms and the Periodic Table

Chemical Bonding

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Liquids, solids, and Intermolecular Forces

Solutions

Acids and Bases

Chemical Equilibrium

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Exam 6: Chemical Composition

A 500.gram iron ore sample was determined to contain 242 grams of iron.What is the mass percent of iron in the ore?

What is the mass (in grams)of 3.03 × 1024 molecules of carbon dioxide molecules?

A 7.96 gram sample of silver reacts with oxygen to form 8.55 gram of the metal oxide.What is the formula of the oxide?

One mole of nitrogen gas contains (2)× (6.022 × 1023)nitrogen atoms.

What is the mass percent of oxygen in sodium oxide?

How many moles of carbon are in 3.5 moles of calcium carbonate?

Mass is used as a method of counting atoms.

What is the mass of sulfur atoms?

What is the molecular formula of a compound given the molar mass of the compound is 30.04 gram and the empirical formula is NH?

Avogadro's Number is 6.022 × 1023.

What is the mass (in grams)of 1.95 moles of water ?

How many molecules of nitrogen monoxide are in a 22.5 gram sample?

An empirical formula gives the specific number of each type of atom in a molecule.

The mass of 2.0 moles of H2O is greater than the mass of 1.0 mole of CO2.

One half of a mole of atoms would contain how many atoms?

A compound composed of only hydrogen and oxygen is 5.94% hydrogen by mass.The molar mass of this compound is 34.02 g/mol.What is the compound's molecular formula?

The chemical formula CH2O can be classified as:

Which of the following compounds has the highest mass percent of "O"?

The numerical value of the mole is defined as being equal to the number of atoms in exactly 12 grams of pure carbon-12.

One mole of CO2 gas contains 1 mole of carbon atoms and 2 moles of oxygen atoms.

The Chemical World

Measurement and Problem Solving

Matter and Energy

Atoms and Elements

Molecules and Compounds

Chemical Reactions

Quantities in Chemical Reactions

Electrons in Atoms and the Periodic Table

Chemical Bonding

Gases

Liquids, solids, and Intermolecular Forces

Solutions

Acids and Bases

Chemical Equilibrium

Oxidation and Reduction

Radioactivity and Nuclear Chemistry

Organic Chemistry

Biochemistry

Filters

What is the mass (in grams)of 3.03 × 10²⁴ molecules of carbon dioxide molecules?

One mole of nitrogen gas contains (2)× (6.022 × 10²³)nitrogen atoms.

Avogadro's Number is 6.022 × 10²³.

The mass of 2.0 moles of H₂O is greater than the mass of 1.0 mole of CO₂.

The chemical formula CH₂O can be classified as:

One mole of CO₂ gas contains 1 mole of carbon atoms and 2 moles of oxygen atoms.