# Enthalpy

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Enthalpy of Formation
The enthalpy change when one mole of compound is formed from its constituent elements under standard conditions with all species in their standard states.
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Enthalpy of combustion
The enthalpy change when one mole of substance in burnt completely in oxyen under standard conditions with all products and reactants in their standard states.
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Hess' Law
The total enthalpy change of a reaction is always the same no matter which route is taken.
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Calculatin mean bond enthalpies
Energy release (products) - Energy absorbed (reactants)
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Two things you need to know to measure enthalpy change?
Number of moles of the substance and temperature change
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Enthalpy equation
q = mc^t
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When working out enthalpy changes with q=mc^t you...
use the formula, then work out moles, then divide the two
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In a formation triangle the arrows go
Up
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In a combustion triangle the arrows go
Down
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## Other cards in this set

### Card 2

#### Front

The enthalpy change when one mole of substance in burnt completely in oxyen under standard conditions with all products and reactants in their standard states.

#### Back

Enthalpy of combustion

### Card 3

#### Front

The total enthalpy change of a reaction is always the same no matter which route is taken.

### Card 4

#### Front

Energy release (products) - Energy absorbed (reactants)

### Card 5

#### Front

Number of moles of the substance and temperature change