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3 years ago

How many moles of PBr3 contain 3.68 x 10^25 bromine atoms?

2 answers:

7 0

<span>3.68 x 10²⁵ bromine atoms * 1mol/6.02*10²³ atoms=
= 61.13 mol of bromine atoms

1 mol PBr3 ----- 3 mol Br
x mol PBr3 -----61.13 mol Br

x= 1*61.13/3 = 20.4 mol PBr3.

</span>20.4 mol PBr3 <span>contain 3.68 x 10^25 bromine atoms.</span>

emmainna [20.7K]3 years ago

3 0

Answer:

20.4 moles of $PBr_{3}$ contain $3.68\times 10^{25}$ bromine atoms

Explanation:

1 molecule of $PBr_{3}[/tex contains one P atom and three Br atomsSo 1 mol of [tex]PBr_{3}[/tex contains 3 moles of Br.We know that 1 mol = [tex]6.023\times 10^{23}$ molecules

So, there are $(3\times 6.023\times 10^{23})$ atoms of Br in 1 mol of $PBr_{3}$

Hence $3.68\times 10^{25}$ bromine atoms are present in $\frac{3.68\times 10^{25}}{3\times 6.023\times 10^{23}}$ moles of $PBr_{3}$ or 20.4 moles of $PBr_{3}$

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