Use the following information to find Hf of ethanol [CH3CH2OH(l)]. CH3CH2OH(l) + 3 O2(g) 2 CO2(g) + 3 H2O(g)

Hcomb = -1406.8
Hf of CO2(g) = -393.5 kJ/mol
Hf of H2O(g) = -241.8 kJ/mol

Which statement best explains the relationship between an area is geography and the temperature of its surface water

Achemistry student needs to standardize a fresh solution of sodium hydroxide. he carefully weighs out of oxalic acid , a diprotic acid that can be purchased inexpensively in high purity, and dissolves it in of distilled water. the student then titrates the oxalic acid solution with his sodium hydroxide solution. when the titration reaches the equivalence point, the student finds he has used of sodium hydroxide solution.calculate the molarity of the student's sodium hydroxide solution. be sure your answer has the correct number of significant digits.

The number at the end of an isotope’s name is the number.