Chem100 Exam One Review

Scientific Notation and Sig Figs

100

How many significant figures are in this number?

80000

one

200

Write this number in standard notation.

5.05 x 10⁴

50,500

300

How many significant figures are in this number?

0.0046007020

eight

400

Write this number in scientific notation.

0.006002

6.002 x 10^-3

500

Write this number in scientific notation to five significant figures. What metric prefix is this?

4,211,003

4.2110 x 10⁶

mega

Vocabulary

100

What is an element?

A substance in its most pure form that cannot be broken down any further

200

What is the difference between an atom and a molecule?

An atom is singular, a molecule is one or more atoms combined together

300

Give two examples of a physical property.

density

mass

melting point

boiling point

400

Give two examples of a chemical property.

flammability

toxicity

reactivity

oxidation states

500

What is the difference between a heterogeneous and homogeneous mixture? Give an example of both.

Heterogeneous is a mixture not uniform in composition; seawater and mud or a chunky smoothie. 

Homogeneous is a mixture uniform in composition; sugar dissolved in water.

Metric Prefixes

100

10^-3

milli

200

micro

10^-6

300

giga

10⁹

400

10²

hecto

500

10 ^-12

pico

Unit Conversions

100

Change 16.8 seconds into picoseconds.

168 x 10¹¹ picoseconds

200

Convert 3.301 Volts into kilovolts.

0.003301 kV

3.301 x 10³ kV

300

Convert one mile into centimeters.

160,934 cm

400

Convert 7892.0 feet into millimeters. Round your answer to three significant figures.

2405481.6 mm

2,410,000 mm

2.41 x 10⁶ mm

500

Convert 67 pounds into milligrams. Write your answer in scientific notation with three significant figures.

30,390,688.8 Milligrams

3.04 x 10⁷ mg

Mass, Volume, and Density

100

What is the formula for density?

mass/volume=density

200

What is the difference between mass and weight?

Mass is the amount of something independent of the temperature. Weight is the mass affected by gravitational pull

300

What is the most dense form of matter? What is the least dense?

solid, gas

400

Find the density of a piece of an unknown metal that has a mass of 22.0 kilograms and a volume of 56 liters. Round your answer to two significant figures and use scientific notation.

392.857 g/L

3.9 x 10² g/L

500

Find the mass of a 78 mL solution that has the density of 0.286 g/L at 25 degrees Celsius. Round the answer to three significant figures and put it into scientific notation.

(0.286 g/L) x (78 mL) x (1 L/1000 mL) = 0.022308 g

2.23 x 10^-2 grams