Use the experimental data from Video 2 to calculate the percent copper in brass by mass. Write out your equations with correct units and EXPLAIN why and how you determined the mass percentage. This is from flinn science 2go chemistry lab 6 (stoichiometry) last question based on the second video. the equation based on this is Cu + 4NHO3 ---> Cu(NO3)2 + 2NO2 + 2H2O. i think there is 0.44g of copper

•what conclusions can you make about the relationship between the volume of a gas and its temperature? • what conclusions can you make about the relationship between the volume of a gas and its pressure? • what possible variables have you not accounted for? as you did the procedures, is it possible that the atmospheric pressure may have changed? if it did change over the course of your experiment, then how would your results have been affected?