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4 years ago

Please help this is due today

Chemistry

1 answer:

lara [203]4 years ago

4 0

Answer is: D. ΔH is negative for reaction A and ΔH is positive for reaction B.

There are two types of thermochemical reactions:

1) endothermic reaction (chemical reaction that absorbs more energy than it releases).

For example, ΔH(reaction) = 150 kJ/mol; this is endothermic reaction.

2) exothermic reaction (chemical reaction that releases more energy than it absorbs).

For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.

the change in enthalpy = the total bonding energy for the products of a reaction - the bonding energy of the reactants.

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3 years ago

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Softa [21]

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The number of moles of Ca = 38.7/40.078 = 0.96 mol.

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The number of moles of O = 41.2/15.99 = 2.75 mol.

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Refer to explanation

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3 years ago