Use the law of conservation of the mass to explain how you know that the atoms make up all matter in the universe today are the same atoms that have existed since the universe began.

Calculate the approximate enthalpy change, ΔHrxn, for the combustion of methane: CH4+2O2→2H2O+CO2 ΔHrxn from a given table: CH4 = 1656 kJ/mol O2 = 498 kJ/mol H2O = 928 kJ/mol CO2 = 1598 kJ/mol ΔHrxn = [ (1656) + (2*498) ] - [ (2*928) + (1598) ] =

How many centimeters are in 25 kilometers? A. 2.5 x 10 to the power of 6 B. 2.5 x 10 to the power of 4 C. 2.5 x 10 to the power of 3 D. 2.5 x 10 to the power of 5

How many moles are in 8.30x10^23 molecules of H2o

During which of the following processes does a glucose molecule break down into ethanol? Aerobic respiration, Alcoholic fermentation, Lactic acid fermentation, Photosynthesis

What is 29383.0398 to the nearest hundredth?

Consider the following equation. 2H2 (g) + O2 (g) 2H2O (g); ΔH is negative. Which statement is true? The reaction is endothermic from left to right. Increased pressure would increase the rate of forming water vapor.

Ions form when atoms gain or lose protons. True or False.

In which of the following aqueous solutions would you expect AgI to have the highest solubility? In which of the following aqueous solutions would you expect AgI to have the highest solubility? 0.038 M NaI 0.050 M AgNO3 0.025 M KI 0.

If the passing of five half-lives leaves 25 mg of a strontium-90 sample, how much was present in the beginning?

Which part of the body does colchicine affect the most