Thermochemical Equations: Heat and Enthalpy Calculations

What does a negative delta H signify in a chemical reaction?

• Heat is absorbed

• Heat is released

• Reaction is at equilibrium

• No heat change occurs

How many moles of CH4 are equivalent to 27.5 grams?

• 1.72 moles

• 2.25 moles

• 2.00 moles

• 1.50 moles

What is the heat released from burning 1.72 moles of methane?

• 1530 K

• 1800 K

• 1000 K

• 2000 K

How does the stoichiometric coefficient of oxygen affect the heat calculation?

• It triples the heat per mole

• It has no effect

• It halves the heat per mole

• It doubles the heat per mole

What amount of heat is produced by 2.48 moles of oxygen?

• 1300 K

• 1200 K

• 1000 K

• 1100 K

What conversion factor is used when calculating the amount of heat from moles of a substance?

• Moles over grams

• Grams over moles

• Heat over moles

• Moles over heat

How many grams of N2 are needed to produce 92.6 K of heat?

• 150 grams

• 166 grams

• 200 grams

• 180 grams

What is the molecular weight used to convert moles of N2 to grams?

• 24.0 g/mol

• 30.0 g/mol

• 32.0 g/mol

• 28.0 g/mol

How many moles of hydrogen are required to produce 92.6 K of heat?

• 5.02 moles

• 3.50 moles

• 4.00 moles

• 6.00 moles

What is the total weight of hydrogen needed to get 92.6 K of heat?

• 10.0 grams

• 15.0 grams

• 8.0 grams

• 12.0 grams