The two most abundant elements in the universe are:

a. Hydrogen and Oxygen

c. Hydrogen and Helium

b. Oxygen and Nitrogen

d. Carbon and Oxygen

Which of the following substances is most likely to be a liquid at room temperature? a. formaldehyde, H₂COH₂CO b. fluoromethane, CH₃FCH₃F c. hydrogen cyanide, HCN d. hydrogen peroxide, H₂O₂H₂O₂ e. hydrogen sulfide, H₂S

Describe how to convert between mass and the number of moles of a substance.

Ammonium carbamate (NH2COONH4) is a salt of carbamic acid that is found in the blood and urine of mammals. At 250.°C, Kc = 1.58 * 10-8 for the following equilibrium: NH2COONH4 (s) ⇌ 2 NH3 (g) + CO2 (g) If 11.51 g of NH2COONH4 is put into a 0.

Consider a 1.24 g mixture of magnesium nitrate and magnesium chloride. After dissolving this mixture in water, 0.500 M silver nitrate is added dropwise until precipitate formation is complete. The mass of the white precipitate formed is 0.419 g.

The radius of a hydrogen atom is 37 pm and its mass is 1.67 * 10-24 g. What is the density of the atom in grams per cubic centimeter? Assume the atom is a sphere with: Volume = (4/3) (3.14) (r^3)

1. Calculate the end velocity of a rocket that traveled 16km in 2 seconds. distance time 2. Calculate the rockets acceleration m with a start velocity of 0m/s and the end velocity from #1 for 10 seconds.

How are linear and nonlinear graphs alike

Uranium nuclei split during nuclear fission true or false

Calculate the mass of 2.25*10^22tungsten atoms.

Which weathering process involves physical forces but not chemical reactions or dissolving of minerals