C) volume
.........
The volume of gas depends on e.g. temperature and pressure.
A pure crystalline substance is a substance with an almost perfect regular and periodic pattern in a solid state. This makes this type of substance a hard one compared to an amorphous substance which is soft because of the irregular pattern within.
<u>Answer:</u> The formula of chromic acid is 
<u>Explanation:</u>
We are given an ionic compound named as chromic acid. This acid is formed by the combination of hydrogen ion and chromate ion.
An acid is defined as the substance which releases hydrogen ion when dissolved in water.
Hydrogen is the 1st element of periodic table having electronic configuration of
.
This element will loose 1 electron to form
ion.
Chromate ion is a polyatomic ion having chemical formula of 
By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.
So, the chemical formula for the given compound is 
Thus, the formula of chromic acid is 
a small cavity or space in tissue, especially in nervous tissue as the result of disease.
<span>Ionic compounds form crystal lattices, not molecules. The term formula unit is used to indicate the simplest whole-number ratio of ions in the compound.</span>