A 2.14-L sample of hydrogen chloride HCl gas at 2.61 ATM and 28C is completely dissolved in 668 mL of water to form hydrochloric acid solution Calculate the molarity of the acid solution Assume n?

Answer 1

Using this ideal gas equation PV=nRT. The question provided the following:

P=2.61 atm

V=2.14L

R=0.0821 ( this is standard for any ideal gas)

T= 28 C+273K= 301

n= unknown

Since there is no volume change, so the volume is constant from the beginning of the reaction to the the end of the reaction. The only key information we are missing is the actual number of moles (n). We must rearrange the ideal gas equation to solve for moles.

n=PV/RT

n=(2.61)(2.14)/(.0821)(301)

n=.2260

The question wants us to find the Molarity of the acid solution. We were given that HCL completely dissolved in 668mL of water.

Molarity moles/Liters.

668mL=.668L

M=.2260mol/.668L

so Molarity of the acidic solution is .338.