If the mass of all the reactants in a chemical reaction is 100g, what will the mass of all products be?

Gymnast always perform on padded mats. how does the mats protect the gymnast

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.)

Which of the following describes qualitative data? a) recording the temperature of a solid as it is warmed. b) noting the color of a solution as it is heated. c) measuring the volume of an object by water displacement. d) taking the mass of an object using a balance.