Recent content by mcnivvitz

  1. M

    CO2 gas in a temp-controlled, pressure-controlled container

    Did the calculation wrong. Now I've got ((.71 mol)(8.3145 J/(mol*kelvin))(-273.15 degrees kelvin)) / (2.0*10^4 cm^3) = -0.795699496 atm Not the right answer for pressure. But at least the proper units.
  2. M

    CO2 gas in a temp-controlled, pressure-controlled container

    Err, I put the wrong units and gas constant. Here: ((.71 mol)(8.3145 J/mol K)(-273.15 degrees K)) / (2.0*10^4 cm^3) = P = -80624251.5 kg K / s2 That's not right either. Sigh.
  3. M

    CO2 gas in a temp-controlled, pressure-controlled container

    P = nRT / V Molar mass of CO is 28.010 g mol^-1. Therefore number of moles in 20 g is 20 g/28.010 g mol^-1 = 0.71 mol. P = ((.71)(8.314472e15)(-273.15)) / (2.0*10^4 cm^3) P = -8.062398*10^19 m^3 Is this correct? What do I do now?
  4. M

    CO2 gas in a temp-controlled, pressure-controlled container

    The problem: 20 g of dry ice (solid CO2) is placed in a 2.0*10^4 cm^3 container, then all the air is quickly pumped out and the container sealed. The container is warmed to 0 deg C, a temperature at which CO2 is a gas. a) What is the gas pressure? Give your answer in atm. The gas then undergoes...
  5. M

    Calorimetry problem involving tea and ice

    I see. Use the specific heat of water instead of ice, since the ice melts. Thank you so much!
  6. M

    Calorimetry problem involving tea and ice

    2050 is the specific heat capacity of ice, although I'm not sure where I got that number... It seems every site I go to has a different value. Wikipedia is saying 2110 So I'll see if that makes a difference. It gives me 17.6, which is still wrong. Any other suggestions?
  7. M

    Calorimetry problem involving tea and ice

    The problem: On a hot summer day, you decide to make some iced tea. First, you brew 1.50 L of hot tea and leave it to steep until it has reached a temperature of T_tea = 75.0 C. You then add 0.975 kg of ice taken from the freezer at a temperature of T_ice = 0 C. By the time the mix reaches...
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