Indicate how the concentration of each species in the chemical equation will change to reestablish equilibrium after a decrease in pressure or volume. If there is no change in the concentration of the species, leave the box blank. CH 4 ( g ) + 2 H 2 S ( g ) − ⇀ ↽ − CS 2 ( g ) + 4 H 2 ( g ) CH4(g)+2H2S(g)↽−−⇀CS2(g)+4H2(g) after decreasing the pressure after decreasing the volume of the reaction vessel

Which describes fat? a: a carbohydrate that produces energy b: a nucleic acid that directs cell function c: a lipid that stores energy d: a protein that speeds up a chemical reaction

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.)

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false