Question

Calculate the number of moles 3.15 g of HNO3 19.3 g of NaCl 21.25 g of NaNO3

Answer 1

The number of moles:
3.15g of $HNO_{3}$
1 mole of $HNO_{3}$- 63g.
x moles of $HNO_{3}$- 3.15g
$x=\frac{1\ mole*3.15g}{63g}=\frac{3.15}{63}=0.05\ mole$

The number of moles:
19.3 g of NaCl
1 mole of NaCl- 58.44g.
x moles of NaCl- 19.3g.
$x=\frac{1\ mole*19.3g}{58.44g}=\frac{19.3}{58.44}=0.33\ mole$

The number of moles:
21.25 g of $NaNO_{3}$
1 mole of $NaNO_{3}$- 85g.
x moles of $NaNO_{3}$- 21.25g.
$x=\frac{1\ mole*21.25g}{85g}=\frac{21.25}{85}=0.25\ mole$

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