How many molecules are there in 6.73 moles of phosphorus trichloride? (write your answer in scientific notation).
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Answer: There are [tex]4.05\times 10^{24}[/tex] molecules in 6.73 moles of phosphorus trichloride
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
1 mole of [tex]PCl_3[/tex] contains = [tex]6.023\times 10^{23}[/tex] molecules
Thus 6.73 moles of [tex]PCl_3[/tex] contains = [tex]\frac{6.023\times 10^{23}}{1}\times 6.73=4.05\times 10^{24}[/tex] molecules
Thus there are [tex]4.05\times 10^{24}[/tex] molecules in 6.73 moles of phosphorus trichloride