#1. You have a solution of concentration 17.4 moles/liter. You want to dilute that to 1.5 moles/liter. You can figure out how many moles will be in the final solution and how much of the original solution to measure out. If you multiply Moles/Liter times Liters, the Liters will cancel out and you'll have moles.

#2.

is the ideal gas law. P=pressure, V=volume, n=number of moles, T=absolute temperature. R is the "universal gas constant". You can Google it.

#3. Same equation.

#4. Calculate the number of moles of N2 and CO2. That's what causes the pressure. 1 mole of KNO3 generates 2 moles of gas (from the equation) -- one mole of CO2 and one mole of N2. Calculate the molecular weight of KNO3 (Grams/Mole) and divide the number of grams you have by the molecular weight

You'll find from the ideal gas law (plug in the temperature and pressure and solve for the volume) that at STP, 1 mole occupies 22.4 Liters.