please help me with these questions.

4. How many grams of CH, gas will occupy a volume of 5.67L at 35C and 766torr pressure? 5. A helium filled balloon has a volume of 5.00L at 27C. What will be the volume at -93C at the same pressure? 6.A 13.0L tank used in scuba diving was filled with air at a pressure of 115atm. What volume will the air occupy at a pressure of 775tor at the same temperature? 7. What volume will 150.mL of neon gas at 23C and 710tort occupy at STP? 8. Calculate the density of SF, gas at 707torr and 21C 9. Calculate the molar mass of a gas that has a density of 7.135g/L at 12 and 743tor 10. 2CH() +250(g) 1600,(g) + 18H (I) Calculate the mass of CH needed to produce 4.SOL of Co gas at 28 and 1.20atm pressure (Ignore vapor pressure of water) 11. Mg + 2HCl(aq) MgCl(aq) + H (8) Calculate the volume of H gas collected at 24C and 740.mm Hg pressure from the reaction of 22.56g Mg with excess HCI