Copper is added to a solution of nitric acid. the solution becomes hot and changes from colorless to dark blue. what is the best explanation for the change in temperature?
a.
the copper and nitric acid repel each other, which produces heat.
b.
the chemical reaction between the copper and the nitric acid produces heat.
c.
the blue color absorbs less energy, which causes heat to be released.
d.
the increased volume of the solution causes heat to be released.

Which statement accurately describes the relationship between air pressure, air density, or altitude? as altitude increases, pressure increases.as altitude increases, air density increases.air pressure and density are lowest at sea level.denser air exerts more pressure than less dense air.

Listen base your answer to the question on the information below.propane is a fuel that is sold in rigid, pressurized cylinders. most of the propane in a cylinder is liquid, with gas in the space above the liquid level. when propane is released from the cylinder, the propane leaves the cylinder as a gas. propane gas is used as a fuel by mixing it with oxygen in the air and igniting the mixture, as represented by the balanced equation below.c3h8(g) + 5o2(g) → 3co2(g) + 4h2o() + 2219.2 kja small amount of methanethiol, which has a distinct odor, is added to the propane to consumers detect a propane leak. in methanethiol, the odor is caused by the thiol functional group (–sh). methanethiol, ch3sh, has a structure that is very similar to the structure of methanol.what is the correct structural formula for a molecule of methanethiol

Which metal exist in liquid state and can be cut with knife ?