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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: Sam_95 on February 14, 2012, 07:49:52 pm

Title: Few Mole Questions, Help Please!
Post by: Sam_95 on February 14, 2012, 07:49:52 pm: Q1. CO2 is added to 1.00 L of pure water at 25°C in a pressurised bottle. The pressure of CO2 above the water was raised to 3.00 atm and the gaseous CO2 came to equilibrium with the CO2 dissolved in the water. At equilibrium, the mass of CO2 dissolved in the water was 5.00 g.

500 mL of the aqueous solution of CO2 is heated to 30°C and then opened to the atmosphere so that effectively all the CO2 in the aqueous solution escapes into the gas phase. Calculate, in litre, the volume of CO2 that would be evolved at 1.00 atm pressure and 30°C.

Q2. A 100 mL sample of helium exerts a pressure of 1 atm at 10°C. The volume of the container is reduced to 50 mL and then the temperature is increased to 20°C.

The pressure now exerted by the helium, in atmosphere, is closest to?

Q3. Equal masses of the two gases oxygen (O2) and sulfur dioxide (SO2) are placed in separate vessels. Both vessels have the same volume and are at the same temperature. The pressure exerted by the oxygen is 100 kPa.

The pressure, in kPa, exerted by the SO2 is closest to?

Q4. The molar volume of oxygen, in L, at 1.00 atmosphere and 100°C, is closest to?

Q5. Different quantities of nitrogen oxide (NO) are listed below.
Which one contains the least number of molecules?
Title: Re: Few Mole Questions, Help Please!
Post by: Studyinghard on February 14, 2012, 11:58:44 pm: Just posting your homework questions wont get anyone to help you out. You have to show where you tried and where you got stuck.
Title: Re: Few Mole Questions, Help Please!
Post by: Phy124 on February 15, 2012, 04:07:36 am: Hi Sam, Studyinghard is right, try and make and attempt at a few of the questions and we will be more inclined to help ;)

I suggest you get to know the gas equation, $PV = nRT$ well and be able to derive equations from this such as $\frac{P_{1}V_{1}}{T_{1}}=\frac{P_{2}V_{2}}{T_{2}}$ . This will have you well on your way to being able to successfully complete these questions without our aid :)

Don't feel inclined not to put working out under a question because you are afraid we will think of less of you, I and many others prefer to see wrong working out rather than none at all ;)