For the Earth's atmosphere, section number two in the pie graph BEST represents the percentage of A) argon B) oxygen C) nitrogen D) carbon dioxide.

Which of the following is an indication that a substance has undergone a chemical change?

Which statement best describes how to predict the formula of a stable ionic compound? a Use the same number of cations as anions so that the compound is neutral. b Use more cations than anions so that the compound is positively charged.

8. How do you know when kinetic energy is not changing?

In which location would a free neutron from a decaying U-235 atom be most likely to cause another atom to go split? A. In a sample of naturally occurring uranium B. In a sample of enriched uranium C. In a sample of rock or soil D.

Which statement is true about trends shown on the electromagnetic scale. A. As wavelength decreases, radiant energy and frequency increase B. As frequency decreases, radiant energy and wavelength increase C.

What causes lightning? a) thunder b) an electric discharge c) rising warm air d) air masses meeting

In a problem, you are given two pressures and one temperature at constant volume and amount of gas. You are asked to find a second temperature. What law should you use?

How many cups are in a 5-lb. bag of flour?

How is oxygen separated from other substances nearby?

What is the definition of solution in chemistry