Answer:
The final volume of the sample of gas
= 0.000151 
Explanation:
Initial volume
= 200 ml = 0.0002
Initial temperature
= 296 K
Initial pressure
= 101.3 K pa
Final temperature
= 336 K
Final pressure
= K pa
Relation between P , V & T is given by

Put all the values in the above equation we get

= 0.000151 
This is the final volume of the sample of gas.
To answer this question you need to know how to calculate the molecular weight of a molecule. The compound is having 1 Mg atom and 2 Cl atom, thus the molecular weight should be:
24.305+ 2*35.453= <span>95.211 gram/mol.
Then, the mass of 3 mol of MgCl would be:
3 mol * 95.211 gram/mol= 285.633 gram</span>
Answer:
There are 3 isomers so the answer is C) 3