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When determining the energy of a reaction where 0.250 mol of a substance with a Hcomb = -2250.0 kJ/mol reacts, we perform this calculation:
-2250.0 kJ/1 mol = x kJ/0.250 mol OR 0.250 mol (-2250.0 kJ/ 1 mol)
Why can't we simply say that the energy of the reaction is -2250.0 kJ?
A student is determining the enthalpy of solution for ammonium nitrate by adding ammonium nitrate to a calorimeter and measuring the temperature change.
The accepted value is Hsol'n = 25.7 kJ/mol
A student, not paying attention, adds 1.5g of ammonium nitrate instead of 1.0g. When they perform their calculations, they use 1.0g as the mass.
Will their calculation result in an answer that is higher than the accepted value or lower? Explain.
The metal thorium becomes superconducting at temperatures below 0.1 K. Calculate the temperature at which lutetium becomes superconducting in degrees Celsius. Round your answer to 1 decimal place.
Benzene has a heat of vaporization of 30.72 kJ/mol and a normal boiling point of 80.1 ∘C. At what temperature does benzene boil when the external pressure is 410 torr?
Propane has a normal boiling point of −42.0∘C and a heat of vaporization (ΔHvap) of 19.04 kJ/mol. What is the vapor pressure of propane at 30.0 ∘C?Express the pressure in torrs to three significant figures.
How much heat is evolved in converting 1.00 mol of steam at 150.0 ∘C to ice at -45.0 ∘C? The heat capacity of steam is 2.01 J/(g⋅∘C) and of ice is 2.09 J/(g⋅∘C).Express your answer in units of kilojoules. Assume the system is at atmospheric pressure.
Calculate the enthalpy of the following reaction:
2Mg + O2 > 2MgO
Given:
Mg + 2HCl > MgCl2 + H2. H=-21.0 kJ
MgO + 2HCl > MgCl2 + H2O. H=-33.5 kJ
H2 + 1/2 O2 > H2O. H=-76.0 kJ
What is the partial pressure of nitrogen dioxide if the partial pressure of carbon dioxide is 795 psi ?
how much would the temperature of 275g of water increase if 36.5kj of heat were added
How to measure the CO2 concentrations present in the air...?
