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3 years ago

Predict whether the following reactions will be exothermic or endothermic.

Chemistry

1 answer:

Solnce55 [7]3 years ago

5 0

Answer:

A. N₂(g) + 3H₂(g) -----> 2NH₃ exothermic

B. S(g) + O₂(g) --------> SO₂(g) exothermic

C. 2H₂O(g) --------> 2H₂(g) + O₂(g) endothermic

D. 2F(g) ---------> F₂(g) exothermic

Explanation:

The question says predict not calculate. So you have to use your chemistry knowledge, experience and intuition.

A. N₂(g) + 3H₂(g) -----> 2NH₃ is exothermic because the Haber process gives out energy

B. S(g) + O₂(g) --------> SO₂(g) is exothermic because it is a combustion. The majority, if not all, combustion give out energy.

C. 2H₂O(g) --------> 2H₂(g) + O₂(g) is endothermic because it is the reverse reaction of the combustion of hydrogen. If the reverse reaction is exothermic then the forward reaction is endothermic

D. 2F(g) ---------> F₂(g) is exothermic because the backward reaction is endothermic. Atomisation is always an endothermic reaction so the forward reaction is exothermic

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Vadim26 [7]

Answer:

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Explanation:

Step 1:

The unbalanced equation:

AsO2−(aq) + 3 Mn2+(aq) + H2O(l) → As(s) + MnO4−(aq) + H+(aq)

Step 2:

Balancing the equation.

AsO2−(aq) + 3Mn2+(aq) + H2O(l) → As(s) + MnO4−(aq) + H+(aq)

The above equation can be balanced as follow:

There are 3 atoms of Mn on the left side of the equation and 1 atom on the right side. It can be balance by putting 3 in front of MnO4− as shown below:

AsO2−(aq) + 3Mn2+(aq) + H2O(l) → As(s) + 3MnO4−(aq) + H+(aq)

There are 12 atoms of O on the right side and a total of 3 atoms on the left side. It can be balance by putting 5 in front of AsO2− and 2 in front of H2O as shown below:

5AsO2−(aq) + 3Mn2+(aq) + 2H2O(l) → As(s) + 3MnO4−(aq) + H+(aq)

There are 4 atoms of H on the left side and 1 atom on the right side. It can be balance by putting 4 in front of H+ as shown below:

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Answer:

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Answer:

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Explanation:

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2 years ago

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