What type of change occurs when water changes from a solid to a liquid? A. a phase change B. a physical change C. an irreversible change D. both a and b

What can be described as the breaking of old bonds and forming of new ones? A. chemical reaction B. atomic state C. conduction D. induction

What is a correct expression of the law of conservation mass

Compare the mass of the Mg ribbon with the mass of the magnesium oxide. Notice that the the mass of the magnesium oxide is greater than the mass of the Mg. How do you account for this apparent increase in mass?

Which equation shows conservation of mass and energy for a reaction at 101.3 kpa and 298 k? a. 2h2 (g) + o2 (g) 2h2o (g) + 483.6 kj b. 2h2 (g) + o2 (g) 2h2o (l) + 285.8 kj c. h2 (g) + o2 (g) h2o (g) + 483.6 kj d. h2 (g) + o2 (g) h2o (l) + 285.8 kj?

What is the approximate percent yield for this reaction? Ba (NO3) 2 + Na2SO4 - > BaSO4 + 2 NaNO3

In the calvin cycle, why are fewer than six rubp molecules required to fix six molecules of co2?

An atom that loses an electron is called a?

Which family on the periodic table contains elements that already have the octet in their valence energy level? a:family 1 b:family 13 c:family 15 d:family 18?

A scientist measures the pH of some rain water and finds that it is acidic. Which pH corresponds with the acidic quality of the rain water? A. 6 B. 7 C. 8 D. 9

Polyatomic ions formula for calcium iodate