Chemistry

A compound is 40.0% C, 6.7% H, and 53.3% O by mass. Find its empirical formula.

A compound has the empirical formula CH2O and a molar mass of 180.18 g/mol. Find its molecular formula.

Balance the equation: C3H8 + O2 -> CO2 + H2O.

What mass of CO2 forms when 5.00 g of CH4 burns completely?

For N2 + 3H2 -> 2NH3, if 10.0 mol N2 reacts with 20.0 mol H2, identify the limiting reactant and find the theoretical amount of NH3 produced.

Burning 12.0 g of Mg produces 18.1 g of MgO. For 2Mg + O2 -> 2MgO, find the percent yield.

Find the molarity when 5.85 g of NaCl is dissolved to make 0.500 L of solution.

What volume of a 2.00 M stock solution is needed to make 250.0 mL of a 0.150 M solution?

How many moles of gas are in 2.50 L at 1.00 atm and 298 K? Use R = 0.0821 L*atm/(mol*K).

How much heat is absorbed by 100.0 g of water warming from 20.0 °C to 23.5 °C? Use c = 4.184 J/(g*°C).