What is the number of hydrogen atoms present | vedclass

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(C) The chemical formula of urea is $NH_2CONH_2$ or $CH_4N_2O$. The molar mass of urea is $(12 + 4 	imes 1 + 2 	imes 14 + 16) = 60 \ g/mol$. The num

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$2.168 	imes 10^{23}$

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(C) The chemical formula of urea is $NH_2CONH_2$ or $CH_4N_2O$. The molar mass of urea is $(12 + 4 	imes 1 + 2 	imes 14 + 16) = 60 \ g/mol$. The number of moles of urea in $5.4 \ g$ is $n = \frac{5.4}{60} = 0.09 \ mol$. Each molecule of urea contains $4$ hydrogen atoms. Therefore,the number of hydrogen atoms = $n 	imes 4 	imes N_A$,where $N_A = 6.022 	imes 10^{23} \ mol^{-1}$. Number of hydrogen atoms = $0.09 	imes 4 	imes 6.022 	imes 10^{23} = 0.36 	imes 6.022 	imes 10^{23} = 2.16792 	imes 10^{23} \approx 2.168 	imes 10^{23}$.

What is the number of hydrogen atoms present in $5.4 \ g$ of urea?

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