An oxygen tank kept at 20 ◦C contains 28 moles of oxygen and the gauge reads 31 atm. After two weeks, the gauge reads 10.5 atm. How much oxygen was used during the twoweek period? 1. 9.48 mol 2. 9.25 mol 3. 20.5 mol 4. 18.52 mol 5. 7.51 mol

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

Consider the following reaction at equilibrium. 2co2 (g) 2co (g) + o2 (g) h° = -514 kj le châtelier's principle predicts that the equilibrium partial pressure of co (g) can be maximized by carrying out the reaction a. at high temperature and high pressure b. at high temperature and low pressure c. at low temperature and low pressure d. at low temperature and high pressure e. in the presence of solid carbon

The biosphere of the earth is made up of what compound? organic or inorganic?