Question

Calculate the number of particles in i) 23 grams of Na atom [Atomic mass of Na= 23u] ii) 0.2 mole of Carbon atom.

Answer 1

Solution :-

i) 23 grams of Na atom

$Mole = > \frac{given \: mass \: }{molar \: mass \: } \\ \\ Mole \: = > \frac{23}{23} \\ \\ Mole \: = > 1 \: mol \\ \\ Number \: of \: particle \: = > mole \: \times avogadro \: no \\ \\ Number \: of \: particle \: = >1 \times 6.022 \times {10}^{23} \\ \\ Number \: of \: particle \: = >6.022 \times {10}^{23}$

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ii) 0.2 mole of Carbon atom.

$Mole = > \frac{given \: mass \: }{molar \: mass \: } \\ \\ 0.2 \: = > \frac{m}{12} \\ \\ 0.2 \times 12 = > Mass \:\\ \\ 2.4g \: = >Mass \\ \\ Number \: of \: particle \: = > mole \: \times avogadro \: no \\ \\ Number \: of \: particle \: = >0.2 \times 6.022 \times {10}^{23} \\ \\ Number \: of \: particle \: = >1.20\times {10}^{23}$

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