# Chemical Forums

## Chemistry Forums for Students => High School Chemistry Forum => Topic started by: tanishalala on January 21, 2022, 05:02:07 PM

Title: Calculate volume of for molarity solution with 1gr of PH3
Post by: tanishalala on January 21, 2022, 05:02:07 PM
Question attached as image. Thanks in advance. Sorry for the bad translation. I can’t solve B
Title: Re: Calculate volume of for molarity solution with 1gr of PH3
Post by: Borek on January 21, 2022, 05:49:46 PM
Looks like a trivial stoichiometry, what have you tried and why it didn't work?
Title: Re: Calculate volume of for molarity solution with 1gr of PH3
Post by: tanishalala on January 21, 2022, 06:03:09 PM
Looks like a trivial stoichiometry, what have you tried and why it didn't work?

So I tried:
Calculating the Volume so I could use M1V1=M2V2
But I don’t know how to calculate the volume. Also converted PH3 to moles (0,0294) but not sure what to do with it next. The moles I converted is with the molair mass of PH3 divided by the one gram. Tried dividing it with 4 since the ratio PO3 with PH3 is 4. So I’m not really sure if I’m close to anything but I really really can’t figure it out..
I tried so many more things but erased them out of frustration sorry.
Title: Re: Calculate volume of for molarity solution with 1gr of PH3
Post by: Borek on January 22, 2022, 03:56:03 AM
Calculating the Volume so I could use M1V1=M2V2

There is no dilution here, I am afraid this formula won't help.

Quote
converted PH3 to moles (0,0294)

Good starting point.

Look at the reaction equation: how many moles of the starting material is required to produce that number of moles of PH3?

Do you know any formula that combines number of moles, volume and concentration of the substance?
Title: Re: Calculate volume of for molarity solution with 1gr of PH3
Post by: sjb on January 22, 2022, 12:29:17 PM