The enthalpies of formation of the compounds in the combustion of methane,
ch4 (9)+20,(g) → c02(g) +2h2o(g),
are ch4(g): ah = -74.6 kj/mol; co2(g): ah+ = -393.5 kj/mol; and h2o(g): ahp= -241.82 kj/mol.
how much heat is released by the combustion of 2 mol of methane?
use ah xn=(ahi products) - (ahereactants).
-80.3 kj
-802.5 kj
o-1,605.1 kj
o -6,420.3 kj

13. calculate the initial concentration (before precipitation) of carbonate ions after the addition of each 0.05 ml of solution b to the 1.00 l beaker of solution a. divide the work among group members and write the answers in the table in model 3. assume the volume change as solution b is added is negligible. 14. notice the initial concentrations of zn2+ - and cu2+ in the table in model 3. a. explain how these were obtained from the data in model 2. b. as solution b is added and precipitates form, do these initial concentrations change? 15. use the data in model 2 to indicate the presence of precipitate (either znco3 or cuco3) after each 0.05 ml addition of solution b in model 3. 16. use the initial concentrations of carbonate ions and zinc ions to calculate the reaction quotient, qsp for the zinc carbonate scenarios in model 3. divide the work among group members and write the answers in the table in model 3. 17. use the initial concentrations of carbonate ion and copper(ii) ions to calculate the qsp for the copper(ii) carbonate scenarios in model 3. divide the work among group members and write the answers in the table in model 3.

An empty fuel tank can still contain and therefore can be even more dangerous than one full of liquid fuel.

Iron (3) oxide will decompose in the presence of hydrogen gas and heater to produced iron and digydrogen monoxide white a balanced chemical equation