Which of the following contains ionic bonding? (2 points) select one: a. naoh b. n2o4 c. no3- d. no2

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.)

You open a can of soda at room temperature and hear a hiss. which of the following factors has changed inside the container? a.) atmospheric pressure b.) temperature of gas c.) type of gas d.) amount of gas

Describe the forces both attractive and repulsive that occur as two atoms move closer together.