Which is not a compound?

oxygen gas

water

silicon dioxide

carbon dioxide gas

Helium has two naturally occurring isotopes, helium-3 and helium-4. the atomic mass of helium is 4.003 amu. which isotope is more abundant in nature? explain your answer.

Sodium and chlorine react to form sodium chloride: 2na (s) + cl2 (g) →2nacl (s) part awhat is the theoretical yield of sodium chloride for the reaction of 55.0 g na with 67.2 g cl2?

Which of the following does NOT correctly describe the kinetic molecular theory? Collisions between gas particles are inelastic. Gas particles are small and spherical with an insignificant volume.

What is the correct classification of a mixture in which both a solid and a liquid are visible?

How can the freezing of surface waters make the water that is left unfrozen denser?

1. If 25 grams of carbon dioxide gas is produced in this reaction, how many grams of sodium hydroxide should be produced? NaHCO3 > NaOH + CO2. If 50 grams of sodium hydroxide are produced, what is the percent yield?

G what is the difference between the sidechains of leucine and isoleucine? select one: a. one is charged, the other is not b. one has more h-bond acceptors than the other c.

How many grams of NaOH are needed to make 500 mL of a 2.5 M NaOH solution

During its life cycle, an amphibian lives both on land and in water.

An atom that contains 22 protons, 23 neutrons, and 22 electrons would have a mass of approximately