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Chemistry Reaction and Concepts

I need some help answering these questions.

1. A.What is the mass in grams of 2.75 moles of CH4 ?
B. How many moles are in 365 grams of K2SO4 ?
2. Using the bond energies below determine the value and sign
of delta H for the reaction:
2H-H + O=O → 2H-O-H
Bond energies in kJ/mol: H-H 432.0 O=O 493 H-O 460
3. 2C2H6 + 7O2 → 4CO2 + 6H2O
A. How many moles of O2 are needed to react with 5.00 moles of C2H6?
B. How many grams of H2O result when 85.0g of C2H6 react?
4. When a mole of C9H20 is combusted it reacts with 14 moles of O2
A. How many moles of CO2 are produced ?
B. How many moles of H2O are produced ?

Solution Preview

1. A.What is the mass in grams of 2.75 moles of CH4 ?
Mass: 2.75 mol*16.04 g/mol=44.11 g.
B. How many moles are in 365 grams of K2SO4 ?
Molar amount: 365 g*(1mol/174.26g)=2.09 mol

2. Using the bond energies below determine the value and sign
of delta H for the reaction:
2H-H + O=O → ...

Solution Summary

The solution provides good explanations about how to solve concept and moles based questions.

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