Intro to college chemistry Quiz 02

Which of the following is not a temperature unit?

Kelvin

Degrees Fahrenheit

Degrees Celsius

Joule

Joule

Which of the following is a volume unit?

cm

cubic cm

cm squared

dm

cubic cm

Which of the following is a physical change?

The chopping of a log into sawdust.

What are changes involving one or more new substances to be formed with different properties than the substances that undergoes the change.

Chemical

Physical

Chemical

Which of the following is classified as a homogeneous solution?

Brass (copper mixed with zinc)

Pure water (H2O)

Smog (dirty air)

Limestone

Iron filings (Fe)

Brass (copper mixed with zinc)

Which of the following is classified as homogeneous/ pure substance?

Smog (dirty air)

100% rubbing alcohol (C3H8O)

95% rubbing alcohol (C3H8O + water)

steel (alloy of iron + other elements)

Muddy water

100% rubbing alcohol (C3H8O)

Which of the following is a physical combination of two or more pure substances?

Natural has

Water

Salt

Air

Sugar

Air

A small amount of sugar dissolved in water is an example of a?

Heterogeneous / solution

Homogeneous / solution

Homogeneous / pure substance / element

Homogeneous / pure substance / compound

Heterogeneous mixture

Homogeneous / solution

If matter is uniform throughout and cannot be separated into other substances by physical processes, but can be decomposed into other substances by chemical processes, it is called a(n)?

Homogeneous / solution

Homogeneous / pure substance / compound

Heterogeneous

Homogeneous / pure substance / element

Heterogeneous / solution

Homogeneous / pure substance / compound.

How would you classify methane?

Homogeneous / pure substance / compound

Homogeneous / pure substance / element

Homogeneous / solution

Heterogeneous

Heterogeneous / pure substance / compound

Homogeneous / pure substance / compound

If salt dissolving in water makes a homogeneous solution. Is it possible to recover the salt by physical separation such as evaporation or condensation of the water?

Yes

Which one of the following is often easily separated into its components by simple techniques such as filtering or decanting?

Homogeneous / pure substance / elements

Heterogeneous material

Homogeneous / pure substance / compound

Heterogeneous material

Which of the following describes a chemical compound?

It is homogeneous and can be separated into other substances by a chemical change.

It is a heterogeneous mixture.

It is a homogeneous / solution.

It is homogeneous and can’t be separated into other substances by a chemical change.

It is homogeneous and can be separated into other substances by a chemical change.

Which of the following is a homogeneous / pure substance / compound?

Calcium

Sodium chloride in water

Sodium

Calcium chloride in water

Calcium chloride

Calcium chloride.

Which of the following is endothermic?

A heating pad

An ice pack used for sport injuries

Freezing water (phase change liquid to solid)

Wood burning

Hydrogen exploding

An ice pack used for sport injuries.

Which of the following is a naturally occurring diatomic molecule?

Ar2

Br2

Er2

Cr2

Dr2

Br2

Convert 1.57 kg to cg.

0.157 cg

0.0157 cg

157000 cg

1570 cg

157 cg

157000 cg

Which of the following is a mass unit?

Nanogram

Centiliter

Kilometer

Centimeter squared

Kelvin

Nanogram

Write the following number into scientific notation? 0.00000017

1.7 × 10^-6

1.7 × 10^-5

1.7 × 10^-7

1.7 × 10^6

1.7 × 10^7

1.7 × 10^-7

Which of the following numbers are correctly expressed in both exponential notation and ordinary decimal form?

2.09 × 10^-2 = 409

3.72 × 10^-4 = 0.0000372

62,800 = 6.28 × 10^4

5,910,000 = 5.91 × 10^6

62,800 = 6.28 × 10^4 and 5,910,000 = 5.91 × 10^6