After chemical weathering, the chemical makeup of the weathered rock, is the same as the original, or different?

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.

Analyze the reaction to determine whether the reaction is exothermic or endothermic. explain your reasoning.