Which sample is a pure substance?

A. a test tube of zinc oxide

B. a container of zinc and oxygen

C. a flask of pond water

D. a jar of soil

Ions form when atoms gain or lose protons. True or False.

Which statement best compares a gamma ray to a radio wave?

You gained two pounds while on vacation. Which of the following has changed? A Only your mass has changed B Only your weight has changed C Neither Your Mass nor your weight has changed D Both Your mass and your weight has changed

What element would a metal, like sodium, most likely combine with? magnesium bromine argon silicon

What is the bond angle between the hydrogen atoms in an ammonia (NH₃) molecule?

The agricultural practice of spraying insecticides leaves behind which pollutant in the soil? A. Chemical poison B. Excess nitrogen C. Excess salt D. Acidic compounds

What is the name of the compound composed of iron and carbonate? [hint: iron has a + 3 charge in this compound]?

In a chemical equation the products appear on which side of the equation? A. Left B. Top C. Right D. Bottom

What does the shape of a protein molecule resemble?

Which set of terms best defines what affects kinetic energy and potential energy, respectively? position, gravity gravity, velocity velocity, height height, position