Chemistry Quarter 1 Test

Unit 1

100

How many sig figs are in the measurement:

0.030 mm?

2

200

4.0 g of gas X takes up 2.226 L at standard temperature and pressure.  What is the density of gas X?

1.8 g/L

300

You measure the density of oxygen gas to be 1.60 g/L.  The accepted value for oxygen's density is 1.429 g/L.  What is your percent error?

12.0%

400

What is the mass of a gold cube that measures 3.1 cm on all sides? (Density of gold = 19.3 g/mL)

570 g

500

How many km/hr are in 250.6 cm/s?

9.022 km/hr

Unit 2

100

Is an explosion a physical or a chemical change?

Chemical

200

Elements and compounds are both examples of what?

Pure substances

300

Why does water have a boiling point, but wood does not?

Water is a pure substance, but wood is a mixture of many substances.

400

Which mixture-separation technique is typically used to separate solids from liquids?

Filtration

500

Give three examples of a homogeneous mixture.

Varies (Brass, Steel, Air, Seawater, Gasoline)

Unit 3

100

What was the name of the experiment that led to the discovery of the atomic nucleus?

The Gold Foil Experiment

200

How many valence electrons does phosphorus, P, have?

5

300

Bromine, Br, has two main isotopes:

Br-79  51%

Br-81  49%

What is the average atomic mass of bromine?

79.98 amu

400

What is the number of protons, neutrons, and electrons in ⁶⁷Zn²⁺?

30 p⁺, 37 n⁰, 28 e^-

500

Give the full (unabbreviated) electron configuration for Cesium, Cs.

1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s¹

Grab Bag 1

100

Which was discovered first: the proton, neutron, or electron?

Electron

200

Give an example of an intensive physical property.

Varies (Color, Density, Malleability)

300

How many g/L are in 7.20 g/mL?

7200 g/L

400

What is the difference between accuracy and precision?

Accuracy is the closeness of a measurement to an accepted or defined value.

Precision is consistency among measurements (how close they are to each other).

500

Sunlight is composed of every color of the rainbow, but hydrogen light only produces a few colors.  Why is this?

Electrons can only exist at certain energy levels in an atom, so they can only produce light equal to the energy gaps between the levels.  (different energy = different color)

Grab Bag 2

100

What type of mixture is a smartphone?

Heterogeneous

200

How many milliliters are in 2 kiloliters?

2,000,000 mL

300

How many valence electrons does O^2- have?

8

400

Give the noble gas electron configuration for Krypton, Kr.

[Ar]4s²3d¹⁰4p⁶

500

List out which of these substances would float on each other, from the lowest layer to the highest:

Liquid silver (D = 10.5 g/mL)

A metal block weighing 99 g and measuring 6 cm x 1.5 cm x 0.9 cm

22 mL of honey, weighing 312.4 dg

Metal block, Silver, Honey

(12.2 g/mL, 10.5 g/mL, 1.42 g/mL)