(K+ + MnO4- )+(K+ +Cl- )
This would be a one to one ratio as the charges of each component are equal
You start by diving each quantity given by the atomic wight of each element:
Phosphorus (P) 
Hydrogen (H) 
Then you divide by the lowest number:
for phosphorus
for hydrogen
So the empirical formula will be:

Answer: 
Explanation:
Geometrical symmetry of the molecule and the polarity of the bonds determine the polarity of the molecule.
The molecule that has zero dipole moment that means it is a geometrically symmetric molecule and the molecule which has some net dipole moment means it is a geometrically asymmetric molecule.
As the molecule is symmetric, the dipole moment will be zero as dipole moments cancel each other and the molecule will be non-polar.
As the molecule is asymmetric, the dipole moment will not be zero and the molecule will be polar.
Example: 
Thus, we can say that
is a polar molecule.
The answer is going to be mercury
Assuming that the contents of the chamber ar ideal gases. We can use the relation PV=nRT. At a constant
temperature and number of moles of the gas the product of PV is equal to some
constant. At another set of condition of temperature, the constant is still the
same. Calculations are as follows:
P1V1 =P2V2
P2 = (1)(450)/ 48
P2 = 9.375 atm