AP chem gases

Question

Gas (A) Methane, (B) Ethane, (C) Propane, (D) Butane

Answer 1

4. Average kinetic energy depends only on temperature. So answer is E.

 

5. PV=m/M*RT--ideal gas law. m=d*V, where d is density. So PM=dRT. Product of molar mass M and pressure is greatest for container B, since 4*30=120>2*58=116. Hence answer is B.

 

6. Butane will condense the first, since its molecules move with slowest speed. Answer is D.

Answer 2

Hey Qing -- we may view PV = mRT is an indication of energy [like an air "spring"] ...

 

4) mT is highest with butane [D] ...

5) density is m/V or P/RT ... greatest pressure w/ same T in container [B] ...

6) heaviest stuff usually condenses at lowest P -- we have butane pocket lighters [D] :)