What pressure (in atmospheres) does a gas exert when at 385 mm of hg?

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 statement best describes the liquid state of matter? a. it has definite shape but indefinite volume. b. it has definite shape and definite volume. c. it has indefinite shape and indefinite volume. d. it has indefinite shape but definite volume.

Benzonitrile (c6h5cn) is reduced to two different products depending on the reducing agent used. treatment with lithium aluminum hydride followed by water forms k, which has a molecular ion in its mass spectrum at 107 and the following ir absorptions: 3373, 3290, 3062, 2920, and 1600 cm-1. treatment with a milder reducing agent forms l, which has a molecular ion in its mass spectrum at 106 and the following ir absorptions: 3086, 2850, 2820, 2736, 1703, and 1600 cm-1. l shows fragments in its mass spectrum at m/z = 105 and 77. propose structures for k and l and choose an explanation for how this could be concluded.