AP Chemistry Chapter 1 Self Assessment

A chemist mixes sodium with water and witnesses a violent reaction between the two substances. This is best classified as a(n):

• an observation

• a hypothesis

• a law

• a theory

This image represents a particulate view of a sample of matter. Classify the sample according to its composition.

• The sample is a pure element.

• The sample is a homogeneous mixture.

• The same is a compound.

• The sample is a heterogeneous mixture.

Which change is a physical change?

• wood burning

• iron rusting

• dynamite exploding

• gasoline evaporating

Which property of rubbing alcohol is a chemical property?

• density

  (0.786 g/cm³)

• flammability

• boiling point (82.5°C)

• melting point (–89 °C)

Convert 85.0 °F to K.

• 181.1 K

• 358 K

• 29.4 K

• 302.6 K

Answer explanation

First convert to degrees Celsius and then to Kelvin.

Express 33.2 x 10^-4 m in mm

• 33.2 mm

• 3.32 mm

• 0.332 mm

• 3.32 x 10^-6 mm

Answer explanation

Memorize metric prefixes for this class!

What is the mass of a 1.75 L sample of a liquid that has a density of 0.921 g/mL?

• 1.61 × 10³ g

• 1.61 × 10⁻³ g

• 1.90 × 10^3 g

• 1.90 × 10⁻³ g

Perform the calculation to the correct number of significant figures.

(43.998 × 0.00558) ⁄ 2.002

• 0.121

• 0.12

• 0.12131

• 0.1213

Answer explanation

Answering questions to the correct number of significant figures is required in AP Chemistry.

Perform the calculation to the correct number of significant figures.

(8.01 − 7.50) ⁄ 3.002

• 0.1698867

• 0.17

• 0.170

• 0.1699

Answer explanation

The numerator has two significant figures after you subtracting; thus, the final answer ends up with two sig figs.

Convert 1,285 cm² to m².

• 1.285 × 10⁷ m²

• 12.85 m²

• 0.1285 m²

• 1.285 × 10⁵ m²