III - Thermochemical Eq.

Given the thermochemical equation, calculate the heat evolved when 74.6 g of sulfur dioxide (molar mass = 64.07 g/mol) is converted to sulfur dioxide.

• -115 kJ

• 115 kJ

• -115.39 kJ

• 115.39 kJ

Using the thermochemical eq. given, calculate the heat evolved when 266 g of white phosphorus burns in air.

• -6.47 x 10^3 kJ

• -6468 kJ

• 6.47 x 10^3 kJ

• 6468 kJ

Calculate the heat of RXN using the listed heats of formation.

NOTE: Fluorine gas = 0 kJ/mol

• -1934.59 kJ

• -1934.6 kJ

• -1935 kJ

• -1934 kJ

Use the given standard enthalpies of formation to determine the heat of reaction of the given chemical RXN.

NOTE: Na and hydrogen gas = 0 kJ

• -282 kJ

• -282.0 kJ

• 282 kJ

• 282.0 kJ

Calculate the standard enthalpy of formation for the RXN from the listed standard enthalpies of the substances involved.

• -410.8 kJ

• -411 kJ

• 410.8 kJ

• 411 kJ

The standard enthalpy of formation of propene is +20.6 kJ/mole. Calculate the heat of combustion of one mole of propene. The heats of formation of carbon dioxide gas and water liquid are -394 kJ/mole and -285.8 kJ/mole respectively.

NOTE: Diatomic molecule present in the RXN has 0 kJ standard enthalpy of formation.

• -4120 kJ

• -4120.0 kJ

• 4120 kJ

• 4120.0 kJ

It is a thermodynamic function of a system defined by the equation: H = U + PV

• enthalpy

• internal energy

• pressure

• volume

The change of enthalpy is usually expressed in___________.

• kilojoule

• joule

• kilogram

• newton

Melting of an ice is an example of________________.

• endothermic process

• exothermic process

Formation of water liquid and carbon dioxide from methane is an example of _________________.

• endothermic RXN

• exothermic RXN