General Chemistry (Part 1): Questions of Basic Stoichiometry

The following questions are about the basic stoichiometry. You may think why I wrote chemistry field again? It ain't a fun part of chemistry. Because I know many students get hard with stoichiometry so I put this field once again. But here are questions only. You need to read 'Let's Try to Learn Stoichiometry' at first and continue reading this part then. Here we go....

1. Calculate the empirical formula for a compound with the following percent composition: 23.29% of Mg, 30.72% of S and 45.99% of O.
   
   
2. A saturated hydrocarbon contains 82.66% of carbon. what is its empirical formula and molecular formula?
   
   
3. Calculate of the mass of chloride ion in 1.00 liter of each of the following solutions: a) 10% of NaCl (1.07 g/ml of density); b) 1.00 M NaCl; c) Calculate the molarity of the first solution.
   
   
4. Express the following gas pressures in atmospheres: a) 300 cmHg; b) 380 torr.
   
   
5. Calculate the molarity of each type of ion remaining in solution after 20.0 ml of 6.00 M hydrochloric acid is mixed with 50.0 ml of 2.00 M barium hydroxide.
   
   
6. How would one prepare exactly 300 ml of 5.00 M HCl solution by diluting sufficient 12.00 M stock solution.
   
   
7. Calculate the mass of CuS produced and the concentration of hydrogen ion produced by bubbling excess sulfuric acid into 1.00 liter of 0.10 M copper (II) chloride solution.
   
   
8. A refrigeration tank is holding 5.00 liters of freon gas (C₂C_l2F₂) at room temperature and 3.00 atm of pressure develop a leak. When the leak was discovered and repaired, the tank had lost 76.0 grams of the gas. What was the pressure of the gas remaining in the tank at the room temperature above?
   
   
9. In an auto engine with no pollution controls, about 5% of the fuel (assume 100% octane, C₈H₁₈) is unburnt. Calculate the relative masses of CO and C₈H₁₈ emitted in the exhaust gas. Calculate the relative volumes of these gases.
   
   
10. When 0.75 mole of a solid "C₈" and 2 moles of gaseous oxygen are heated in a seated vessel (bomb), completely using up the reactants and producing only one compound, it is found that when the temperature is reduced to the initial temperature, the contents of the vessel exhibit a pressure equal to half the original pressure . What conclusions can be drawn from these data about the product of the reaction?