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LenaWriter [7]
3 years ago
10

5) answer is A

Chemistry
1 answer:
Burka [1]3 years ago
3 0

Answer:

A)  positive; added

Explanation:

Based on the reaction:

2NaHCO3(s) + 129kJ → Na2CO3(s) + H2(g) + CO2(g)

<em>2 moles of NaHCO3 requires 129kJ to produce 1 mole of Na2CO3, 1 mole of H2 and 1 mole of CO2.</em>

<em />

That means, the energy must be added being, thus, an exothermic reaction. The exothermic reactions have ΔH >0.

Thus, right answer is:

A)  positive; added

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