Which one of the following is not an agent of chemical weathering? proprionic acid
carbon dioxide
acid rain

its proprionic acid which do not cause any hazardous effect on environment it only effect internal body of human if it is ingested.

Explanation:

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."