Question

Calculate the following for 31.5g of HNO3 1) moles 2)molecules 3)total number of moles

Answer 1

Answer:

Given = 31.5 g of HNO3

find:

• moles
• molecules
• total number of atoms ( I guess total number of atoms because in the question we are already finding the no.of moles so I don't think we have to do the same so I'm going to assume it as atoms sorry if I'm wrong:( )

1. molecular mass in one mole of HNO3

= H = 1

= N = 14

= O = 16 × 3 = 48

= 1 + 14+ 48 = 63 g/mol

i) find the no.of moles

no.of moles = given mass × 1 mole

mass in 1 mol of HNO3

= 31.5 × 1 mol

63

= 0.5 moles

ii) no.of molecules = given moles × 6.02× 10^23

1 mol

= 0.5 × 6.02 × 10^23molecules

(Or further simplified)

= 3.01 × 10^23 molecules

iii) no. of atoms = given moles× 6.02× 10^23

1 mol

= 0.5 × 6.02 ×10^23atoms ( Or further simplified)

= 3.01 × 10^23 atoms

hope this helps :)

Answer 2

Answer:

252g

Explanation:

Given that ; moles of HNO3=4, molar mass of HNO3=1+4+16(3)=63g....... To find ; mass of 4 moles of HNO3=63g.... So;.... Mass of 4 moles OF HNO3= 63(4)=252g..... Result : mass of 4 moles of HNO3 = 252 g