What happens to the mass of a sample containing a radioactive element during its half-life?
a. the mass decreases by half. b. the amount of mass is doubled. c. eventually there is no mass at all. d. the mass remains the same.

Predict the reactants of this chemical reaction. that is, fill in the left side of the chemical equation. be sure the equation you submit is balanced. (you can edit both sides of the equation to balance it, if you need to.) note: you are writing the molecular, and not the net ionic equation. > cacl2(aq) + h20(l)

What causes different colors to appear in the sky? the absorption of light by air molecules the reflection of light by bodies of water the greenhouse effect in earth's atmosphere the scattering and reflection of light by dust particles

What type of electromagnetic waves does the human eye see as the colors red blue or green a visible light waves b radio waves c infrared waves d microwaves