how many litres of 0.500M HCL(aq) are needed to react completely with 0.100 mol of Pb(NO3)2, forming a precipitate of PbCl2(s)...please explain

The volume that is needed to react completely with 0.100 mol of lead nitrate is 0.400 L. It is because 2 moles of HCl are required for every mole of lead nitrate.
2 x 0.100 mole Pb(NO₃) = 0.200 mole HCl
0.200 mol HCl = L x 0.500 M

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OlaMacgregor OlaMacgregor · Answer 2 · 2019-08-29T09:47:11+02:00

Explanation:

Molarity is defined as the number of moles present in a liter of volume.

Mathematically, Molarity = [tex]\frac{\text{no. of moles}}{Volume}[/tex]

As it is given that molarity is 0.50 M and no. of moles is 0.1 mol. Hence, we will calculate the volume of given solution as follows.

Molarity = [tex]\frac{\text{no. of moles}}{Volume}[/tex]

0.5 M = [tex]\frac{0.1 mol}{Volume}[/tex]

Volume = [tex]\frac{0.5 M}{0.1 mol}[/tex]

= 5 liter

Thus, we can conclude that 5 liters of 0.500M HCl (aq) are needed to react completely with 0.100 mol of [tex]Pb(NO_{3})_{2}[/tex], forming a precipitate of [tex]PbCl_{2}(s)[/tex].