Which of these best explains why water vapor has more energy than a block of ice?
a) molecules in a gas move faster than in a solid.
b) molecules in a gas move slower than in a solid.
c) molecules in a gas absorb more heat from their surroundings.
d) molecules in a gas absorb less heat from their surroundings.

Option (A) is the correct answer.

Explanation:

It is known that in gases, molecules are held by weak Vander waal forces. As a result, they move far apart from each other and attain high kinetic energy.

This causes more number of collisions between the molecules of a gas.

On the other hand, in a solid substance molecules are much more closer to each other because of strong intermolecular forces of attraction. This causes the solids to have least kinetic energy and definite shape and volume.

Hence, we can conclude that the statement molecules in a gas move faster than in a solid, best explains why water vapor has more energy than a block of ice.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

b.

the accuracy of the data.