Question

How many moles are there in 458 grams of Na2sO4?

Answer 1

Molecular weight of Na2SO4 = 23×2+32×1+16×4=142g
Given weight=458g
No of moles=Given weight/Gram molecular weight .
No of moles=458/142=3 moles.
There are 3 moles in 458 grams of Na2SO4.

Answer 2

Given:

Mass of $Na_2SO_4$ = 458 g

To find:

Number of moles in 458 g of $Na_2SO_4$ = ?

Formula to be used:

Number of moles = $\frac{Given mass}{Molar mass}$

Calculation:

To calculate the molar mass of $Na_2SO_4$, the mass of individual element present in the compound must be known:

Atomic mass of Na = 23. As 2 atoms of sodium are present 2× 23 = 46

Atomic mass of S = 32

Atomic mass of O = 16. As 4 Oxygen atoms are present 4×16 = 64

Thus the Molar mass of $Na_2SO_4$ = 46+32+64 = 142g/mol

As the given mass as well as molar mass is known, number of moles can be calculated as follows:

Number of moles = $\frac{458}{142}$ = 3.22 moles

Conclusion:

Thus it is inferred that 458g of $Na_2SO_4$contains 3.22 moles

Learn more about mole calculation

Calculate number of moles and the number of molecular in 500mg carbon dioxide

brainly.in/question/3144792

Calculate the number of moles in the following. 1) 1.46 metric tones of aluminium 2) 7.9 mg of ca

brainly.in/question/339119