Which is not an example of chemistry research in the field of energy? a. developing rechargeable batteries b. producing hook-and-loop tape c. determining the usefulness of oil from soybean plants d. studying the effects of insulation

1. baking powder is a 1: 1 molar mixture of cream of tartar (khc4h4o6) and baking soda (nahco3). a recipe calls for two teaspoons (a total of 8.0 grams) of cream of tartar. how much baking soda must be added for both materials to react completely?

What are transitions between a liquid and gas called? identify which way they are transitioning

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.)