Calculate the number of atoms in each of the following

(i) 52 moles of Ar

(ii) 52 u of He

(iii) 52 g of He

Asked by Abhisek | 1 year ago |  159

1 Answer

Solution :-

(i) 52 moles of Ar

1 mole of Ar 

\(6.023 \; \times \; 10^{ 23 }atoms\; of\; Ar\)

Therefore, 52 mol of Ar 

\( 52 × 6.023 \; \times \; 10^{ 23 }atoms\; of\; Ar\)

\(3.131 \; \times \; 10^{ 25 }atoms \;of\; Ar\)

(ii) 52 u of He

1 atom of He = 4 u of He

OR

4 u of He = 1 atom of He

1 u of He =\(\dfrac{ 1 }{ 4 }\) atom of He

52 u of He = \(\dfrac{ 52 }{ 4 }\) atom of He

= 13 atoms of He

(iii) 52 g of He

4 g of He = \(6.023 \; \times \; 10^{ 23 }\) atoms of He

52 g of He = \(\dfrac{ 6.023 \; \times \; 10^{ 23 } \; \times \;52 }{ 4 }\)atoms of He

=\(7.8286 \; \times \; 10^{ 24 }\) atoms of He

Answered by Pragya Singh | 1 year ago

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