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# Need moles chemistry help watch

1. The question is:

0.363g of a solid element Y is vaporised at 400K and 100kPa. It’s volume is found to be 47cm^3. Calculate the relative atomic mass of the element and identify which element Y is.

Im using the ideal gas equation but I get a really weird answer

2. Cm^3 needs to be m^3.....
3. (Original post by icequeenTM)
When using the ideal gas equation did you remember to rearrange to find out n?
(Original post by Texxers)
Cm^3 needs to be m^3.....

Yh I did. I changed cm^3 to m^3, kPa to Pa and used the ideal gas constant of 8.314
4. 100,000 * 4.7x10^-5 = n * 8.314 * 400

Calculate n(moles) then do mass/moles to get Mr!
5. (Original post by Westsidegirl)
Yh I did. I changed cm^3 to m^3, kPa to Pa and used the ideal gas constant of 8.314
I got an Mr ot 256... you?
6. (Original post by Texxers)
I got an Mr ot 256... you?
I can’t find it on the periodic table
7. (Original post by Texxers)
I got an Mr ot 256... you?
Well I got 256.85 so 257 but I still don’t know which element it is
8. (Original post by Westsidegirl)
Well I got 256.85 so 257 but I still don’t know which element it is
Lol OFC there is no element with an Mr of 257 😂😂😂. Are you sure this isn't a compound?

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