Stoichiometry?

Question

Alright so I need to calculate the total pressure in the container. Here is the info I have.
1.702307307 mol
200.0 g
50.0 L
800 C

Okay so I know I use PV=nRT but I only have the n, V, and T so for my R do I just use the 8.31 thing.



Also...
On another problem it says "What volume of gas is formed at STP by the decomposition of calcium carbonate with heat?" It doesn't give any data so I don't know what to do?? I have the balanced equation
CaCo3= Co2 +CaO

Any help you can give....Thank you.

Answer 1

Use PV = nRT, but make sure the T is in Kelvin

Use R = 0.08206 L atm / mol K

You need to know how much CaCO3 decomposes in order to determine the volume of gas formed at STP. The question is missing the appropriate value.

Answer 2

Do not use the 8.31 because that does not have the units that you want. Instead use the R that equals 0.08206 L atm / mol K. Just make sure when you are pluging in the numbers that you change the grams to kilograms and the temperature to Kelvin.

With your other problem, you know from the balanced equation how many moles of one compound are needed for other moles of different compounds. Knowing the moles and the grams per mole can allow you to find the STP.

Answer 3

the first proplem : R= 8.31 will do you just fine
the second one
STP give you data of temprature and pressure and assume n=1 from the equation you can calculate the volume by the same princible

Answer 4

1. Use the thing. Just be sure you report your answer in the right UNITS. Each thing is in units of pressure x volume/ temp-# of moles
2. You're right. No tickee, no washee.