Please help! A sample of H2 was collected over water for use in future chemical analyses. A sample of 91.67 mL of H2 was collected over water at 33.77∘C. Total pressure in the collection vessel was 750.37 mmHg. (The vapor pressure of water at this temperature is 39.416 mmHg.) What was the mass of H2 collected?

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.

c. orbital shape i hope this is correct