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

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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