How many moles of O2 needed to produce 11.5 grams of CO2? 1C5H12 + 8O2 --> 5CO2 + 6H2O

Asample of air with a volume of 2.20m3 at a pressure of 105 kpa and a temperature of 30c is cooled to 10c and the pressure is reduced to 75.0 kpa. what is the new volume? 6.9 1.34 2.56 43.0 2.88

Determine the empirical formula for succinic acid that is composed of 40.60% carbon, 5.18% hydrogen, and 54.22% oxygen.

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)