Q: A student measures the speed of a car as $$57\ \mathrm{mph}$$, but the actual speed is $$60\ \mathrm{mph}. $$What is the percent error?

$$\displaystyle \frac{60 - 57}{60} \times 100\% = 5\%$$

Question 1

Which of the following best describes a pure substance?

Accepted Answer

A material with a uniform and unchanging composition

Question 2

Which of the following is a heterogeneous mixture?

Accepted Answer

Whole wheat bread

Question 3

Which statement describes a chemical property?

Accepted Answer

Reacts with acid

Question 4

Which observation best indicates a chemical change?

Accepted Answer

Bubbles form

Question 5

A student mixes two clear solutions and observes the formation of a solid. Which piece of evidence does this provide for a chemical reaction?

Accepted Answer

Formation of a precipitate

Question 6

The Law of Conservation of Mass can be mathematically expressed as:

Accepted Answer

$$m_\mathrm{reactants} = m_\mathrm{products}$$

Question 7

When magnesium reacts with hydrochloric acid in a closed system, the total mass before and after the reaction remains the same. This is an example of:

Accepted Answer

The Law of Conservation of Mass

Question 8

Which process is endothermic?

Accepted Answer

Sublimation of dry ice

Question 9

Compared to the particles in a gas, the particles in a liquid:

Accepted Answer

Move around less

Question 10

Which of the following best explains why liquids take the shape of their container?

Accepted Answer

The attractive forces between particles are balanced by their kinetic energy

Question 11

A solid changing directly to a gas is called:

Accepted Answer

Sublimation

Question 12

Which separation technique is based on differences in boiling points?

Accepted Answer

Distillation

Question 13

Which method would best separate sand from salt water?

Accepted Answer

Filtration

Question 14

Which of the following is NOT a property of liquids?

Accepted Answer

Easy compressibility

Question 15

Which of the following is NOT a major force of interaction between particles in a liquid?

Accepted Answer

Gravitational forces

Question 16

The entropy (disorganization) of a solid is:

Accepted Answer

Lower than the entropy of liquids and gases

Question 17

Which statement about the solid state is FALSE?

Accepted Answer

The intermolecular forces between particles are weak

Question 18

A student measures the speed of a car as $$57\ \mathrm{mph}$$, but the actual speed is $$60\ \mathrm{mph}. $$What is the percent error?

Accepted Answer

$$\displaystyle \frac{60 - 57}{60} 	imes 100\% = 5\%$$

Question 19

Which laboratory instrument should be used to accurately measure 50.0 mL of water?

Accepted Answer

Graduated cylinder

Question 20

Which student is most precise in their measurements of a 20.0 m hallway?

Accepted Answer

Student B: 18.5 m, 18.6 m, 18.5 m

General Chemistry Study Guide: Classification, Properties, States of Matter, Separation, and Lab Skills

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