Practice Quiz

Which of the following is an example of a molecule?

• O2

• Na

• H

• A random assumption

How is 4,300,000 written in scientific notation?

• 4.3 x 10^6 (Correct Answer)

• 4.3 x 10^7

• 4.3 x 10^8

• 4.3 x 10^9

Which of the following best defines density?

• Mass per unit volume

• Volume per unit mass

• Weight per unit volume

• None of the above

Which is a chemical property?

• Reactivity with oxygen

• Density

• Boiling point

• Melting point

Which of the following is a chemical change?

• Dissolving sugar in water

• Cooking an egg

• Boiling water

• Melting ice

What is the mass of a substance in kg, specific heat is 0.5 J/g°C, and the temperature change is 20°C?

• 200 kg

• 400 kg

• 800 kg (Correct Answer)

• 1000 kg

An element has two isotopes, 35Cl (75%) and 37Cl (25%). What is the atomic mass?

• 35.5 amu

• 36 amu

• 37 amu

• 38 amu

What is the formula for sodium sulfate?

• Na2SO4

• NaSO3

• Na2SO3

• NaSO4

What is the name of NaNO2?

• Sodium nitrite (Correct Answer)

• Sodium nitrate

• Sodium nitrogen

• Sodium dioxide

Why are chemicals important in our daily lives?

• They are found in all harmful substances.

• They make up all the materials we use and interact with.

• They are found only in cleaning products.

• The are present only in organic materials.