Question 1

When Mendeleev developed his periodic table,he placed the greatest emphasis on

Accepted Answer

A) the atomic number of the elements. 
B) putting elements with similar properties in the same column. 
C) leaving no holes or blank spaces in the table. 
D) the melting points of the elements. 
A) the atomic number of the elements. 
B) putting elements with similar properties in the same column. 
C) leaving no holes or blank spaces in the table. 
D) the melting points of the elements. B

Question 2

Which set of compounds illustrates the Law of Multiple Proportions?

Accepted Answer

A) CH₄, C₂H₆, C₃H₈ 
B) NO, NH₃, NH₄Cl 
C) H₂O, H₂ 
D) all of these 
A) CH₄, C₂H₆, C₃H₈ 
B) NO, NH₃, NH₄Cl 
C) H₂O, H₂ 
D) all of these A

Question 3

Substance A contains 85% carbon and 15% hydrogen.Substance B contains 85 % carbon and 15% hydrogen.A and B are the same substance.

Accepted Answer

A) True 
 B)False  True

Question 4

All of the following are examples of molecules EXCEPT ________.

Accepted Answer

A) Si 
B) CO 
C) I₂ 
D) NO₂ 
A) Si 
B) CO 
C) I₂ 
D) NO₂

Question 5

Which set of compounds illustrates the Law of Multiple Proportions?

Accepted Answer

A) NH₃, PH₃, AsH₃ 
B) CH₃, CF₃, CCl₃ 
C) NH₃, N₂H₄ 
D) all of these 
A) NH₃, PH₃, AsH₃ 
B) CH₃, CF₃, CCl₃ 
C) NH₃, N₂H₄ 
D) all of these

Question 6

Which of the following changes is NOT an example of green chemistry?

Accepted Answer

A) replacing mercury thermometers with alcohol thermometers 
B) using large amounts of solvents such as benzene, which is a carcinogen 
C) replacing energy from coal-fired power plants with energy from alternative sources 
D) replacing lead in paint with titanium dioxide 
A) replacing mercury thermometers with alcohol thermometers 
B) using large amounts of solvents such as benzene, which is a carcinogen 
C) replacing energy from coal-fired power plants with energy from alternative sources 
D) replacing lead in paint with titanium dioxide

Question 7

Which of the following was NOT explained by Dalton's atomic theory?

Accepted Answer

A) the Law of Conservation of Mass 
B) the Law of Multiple Proportions 
C) the difference between isotopes of an element 
D) the difference between elements and compounds 
A) the Law of Conservation of Mass 
B) the Law of Multiple Proportions 
C) the difference between isotopes of an element 
D) the difference between elements and compounds

Question 8

Recycling of hazardous materials is important.

Accepted Answer

A) True 
 B)False

Question 9

Which philosopher believed that matter was continuous and was not made up of atoms?

Accepted Answer

A) Aristotle 
B) Dalton 
C) Democritus 
D) Lavoisier 
A) Aristotle 
B) Dalton 
C) Democritus 
D) Lavoisier

Question 10

Explain why Mendeleev left gaps in his periodic table of the elements.

Accepted Answer

Mendeleev left gaps in his periodic tabl

Question 11

Distinguish between a compound and a mixture.

Accepted Answer

A compound and a mixture are two differe

Question 12

The Greek word atomos means

Accepted Answer

A) atom. 
B) uncuttable. 
C) invisible. 
D) continuous. 
A) atom. 
B) uncuttable. 
C) invisible. 
D) continuous.

Question 13

Is it always possible to recycle and reuse materials?

Accepted Answer

A) Yes, because atoms cannot be destroyed in a chemical reaction. 
B) Yes, because atoms can only be rearranged in a chemical reaction. 
C) No, because atoms can be changed into other kinds of atoms. 
D) No, if it is financially impractible to do it. 
A) Yes, because atoms cannot be destroyed in a chemical reaction. 
B) Yes, because atoms can only be rearranged in a chemical reaction. 
C) No, because atoms can be changed into other kinds of atoms. 
D) No, if it is financially impractible to do it.

Question 14

John Dalton discovered which of the following laws?

Accepted Answer

A) The Law of Conservation of Mass 
B) The Law of Definite Proportions 
C) The Law of Constant Composition 
D) The Law of Multiple Proportions 
A) The Law of Conservation of Mass 
B) The Law of Definite Proportions 
C) The Law of Constant Composition 
D) The Law of Multiple Proportions

Question 15

The atomic masses for elements are

Accepted Answer

A) actual masses determined by weighing individual atoms. 
B) relative masses determined by comparison with a standard reference. 
C) the same as the atomic number. 
D) unknown. 
A) actual masses determined by weighing individual atoms. 
B) relative masses determined by comparison with a standard reference. 
C) the same as the atomic number. 
D) unknown.

Question 16

For which of the following would recycling of iron NOT be practical?

Accepted Answer

A) old cars that are compressed in junkyards 
B) steel beams that have been removed from a bridge 
C) rust that flakes off a car body 
D) wrought iron fences 
A) old cars that are compressed in junkyards 
B) steel beams that have been removed from a bridge 
C) rust that flakes off a car body 
D) wrought iron fences

Question 17

Antoine Lavoisier is often credited with doing more than anyone else to establish chemistry as a quantitative science.What was the significance of Lavoisier's work?

Accepted Answer

careful me

Question 18

When added to a sealed flask and heated,6.0 g of carbon and 16.0 g of oxygen react to form 22.0 g of carbon dioxide.How much carbon dioxide is formed when 24.0 g of carbon is reacted with 100.0 g of oxygen?

Accepted Answer

A) 40.0 g 
B) 44.0 g 
C) 88.0 g 
D) 112.0 g 
A) 40.0 g 
B) 44.0 g 
C) 88.0 g 
D) 112.0 g

Question 19

Describe what happens in a chemical reaction.

Accepted Answer

The arrang

Question 20

The Law of Definite Proportions was first stated by

Accepted Answer

A) Lavoisier. 
B) Galileo. 
C) Dalton. 
D) Proust. 
A) Lavoisier. 
B) Galileo. 
C) Dalton. 
D) Proust.

Exam 2: Atoms

When Mendeleev developed his periodic table,he placed the greatest emphasis on

Which set of compounds illustrates the Law of Multiple Proportions?

Substance A contains 85% carbon and 15% hydrogen.Substance B contains 85 % carbon and 15% hydrogen.A and B are the same substance.

All of the following are examples of molecules EXCEPT ________.

Which set of compounds illustrates the Law of Multiple Proportions?

Which of the following changes is NOT an example of green chemistry?

Which of the following was NOT explained by Dalton's atomic theory?

Recycling of hazardous materials is important.

Which philosopher believed that matter was continuous and was not made up of atoms?

Explain why Mendeleev left gaps in his periodic table of the elements.

Distinguish between a compound and a mixture.

The Greek word atomos means

Is it always possible to recycle and reuse materials?

John Dalton discovered which of the following laws?

The atomic masses for elements are

For which of the following would recycling of iron NOT be practical?

Antoine Lavoisier is often credited with doing more than anyone else to establish chemistry as a quantitative science.What was the significance of Lavoisier's work?

When added to a sealed flask and heated,6.0 g of carbon and 16.0 g of oxygen react to form 22.0 g of carbon dioxide.How much carbon dioxide is formed when 24.0 g of carbon is reacted with 100.0 g of oxygen?

Describe what happens in a chemical reaction.

The Law of Definite Proportions was first stated by

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