Why Basalt and gabbro are denser than granite and
obsidian?

What do you think causes some rock types to have higher densities than others? (Assuming there are no air pockets in the rock, the types of minerals will determine the density. Granite contains lots of quartz and feldspar - both fairly light minerals, whereas basalt and gabbro are made of heavier minerals.)

Explanation:

the answer is barium and copper bromide

answer : (a) volume of the gas = 8.67 ×   l

                (b) second virial coefficient b = -1.21226 l/mole

solution :   given,     t = 300k

                                p = 20atm

                                z = 0.86

                                n = 8.2 mmoles = 8.2 × moles

                                r =   0.082 l atm/k/mol

        find,     (a) volume of gas   and (b) second virial coefficient b at 300k.

formula used :            

                          and            

(a)            

                    = \times 0.082\times 300}{20}[/tex]

                    = 8.67 ×   l

(b)      

                    = (0.00867-1) × 8.659

                    = - 8.5839 l/mole