Question 1

Which of the following best describes a chemical change?

Accepted Answer

Iron rusting when exposed to air

Question 2

Which statement correctly distinguishes between a compound and an element?

Accepted Answer

A compound can be broken down into simpler substances by chemical reactions, while an element cannot.

Question 3

Which of the following is a homogeneous mixture?

Accepted Answer

Salt dissolved in water

Question 4

Which of the following is NOT a property used to identify a substance?

Accepted Answer

Shape of the container

Question 5

Which of the following best represents a chemical reaction?

Accepted Answer

$$ \mathrm{H_2O(l) \rightarrow H_2$(g) + O_2$(g)} $$

Question 6

A student observes that when sugar is heated in a pan, it turns brown and produces a new smell. What type of change has occurred?

Accepted Answer

Chemical change, because new substances with different properties are formed.

Question 7

Which of the following is a correct chemical formula for a compound containing two hydrogen atoms and one oxygen atom?

Accepted Answer

$$ \mathrm{H_2O} $$

Question 8

Which of the following is an example of a heterogeneous mixture?

Accepted Answer

Salad with lettuce, tomatoes, and cucumbers

Question 9

Which of the following statements about the states of matter is correct?

Accepted Answer

A solid has a definite shape and definite volume.

Question 10

Which of the following is a correct representation of a chemical reaction using symbols?

Accepted Answer

$$ \mathrm{2H_2(g) + O_2$(g) \rightarrow 2H_2O(l)} $$

Question 11

Which of the following is a physical change?

Accepted Answer

Dissolving sugar in water

Question 12

Which of the following is a pure substance?

Accepted Answer

Sodium chloride (table salt)

Question 13

Which of the following is the correct symbol for the element sodium?

Accepted Answer

Na

Question 14

A sample of matter is uniform throughout and can be broken down into simpler substances by chemical means. How should it be classified?

Accepted Answer

Compound

Question 15

Which of the following best describes the scientific method?

Accepted Answer

A process of observation, hypothesis, and experiment used to expand knowledge.

Question 16

Which of the following is a correct statement about chemical formulas?

Accepted Answer

Subscripts in a chemical formula indicate the number of atoms of each element in a molecule.

Question 17

Which of the following is an example of a chemical property?

Accepted Answer

Ability to react with acid

Question 18

Which of the following best describes a gas?

Accepted Answer

It has neither a definite shape nor a definite volume.

Question 19

Which of the following is a correct example of a chemical reaction involving nickel and hydrochloric acid?

Accepted Answer

$$ \mathrm{Ni(s) + 2HCl(aq) \rightarrow $$NiCl_2$$(aq) + H_2$(g)} $$

Question 20

Which of the following is a correct classification for vanilla ice cream?

Accepted Answer

Homogeneous mixture

Chapter 1: Matter and Measurements – Fundamentals of General, Organic, and Biological Chemistry

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