pumice is volcanic rock that contains many trapped air bubbles. a 225 gram sample occupied 236.6 mL. What is the denisty of pumice.

Which phrase accurately describes what living organisms strive for? A. Fluctuating internal temperatures B. Continuous change within system parts C. No response to different external conditions D. Stable internal enviroment

Which of the following is NOT a physical property? A) Water boiling at 100°C B) A mineral causing a white streak on another mineral C) Sodium exploding when mixed with water D) A piece of styrofoam floating on water because it is less dense

Which of these is NOT a source of the extra nutrients that would contribute to cultural eutrophication? A. farms B. golf courses C. factory emissions D. water treatment plants

Suppose you give an ideal gas some amount of heat, Q, in one of two ways: one is to keep the gas at constant pressure, so you allow it to expand (and therefore do some work) in the process.

What is change in atomic number when an atom emits positron?

Does skin have a nucleus true or false

Bacteria are only found in decaying matter. A. True B. False

Which is considered a chemical mutagen? tanning beds tobacco X-rays precious metals

Combining 0.380 mol Fe2O3 with excess carbon produced 13.7 g Fe Fe2O3 + 3C → 2Fe + 3CO What is the actual yield of iron in moles? What is the theoretical yield of iron in moles? What is the percent yield?

When a hydrogen electron makes a transition from n=3 to n=1?