One of the problems with using hydrogen gas as a fuel to power cars is that it must be stored in high pressure tanks. The high pressure tanks that would be required to take a car a reasonable distances between refuelling stops are often far too large for the average vehicle. What would be the necessary internal volume of a tank that stored hydrogen at 20.0 atm, if you needed to store enough hydrogen to react with 1435 g of oxygen gas at 32oC according to the chemical equation below? 2 H2(g) + O2(g) H2O(g)

Which element forms an ionic bond with flourine? 1) fluorine 2) carbon 3) potassium 4) oxygen

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.

What can be found in the ionosphere