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4 years ago

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A scientist is studying a previously unknown chemical reaction. She concludes that it is exothermic. What must the scientist hav

e observed?
The reaction released heat.
The reaction formed a gas.
The reaction sped up when a catalyst was added.
The reaction caused the container to get cold.

2 answers:

SVEN [57.7K]4 years ago

6 0

I think the correct answer from the choices listed above is the first option. She concluded that the reaction is an exothermic one because t<span>he reaction released heat. Exothermic is when heat goes out of the system. The opposite is referred to as an endothermic reaction.</span>

Ann [662]4 years ago

6 0

A. <span>The reaction released heat.</span>

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Removing the common ions present ion both the sides, we get the net ionic equation for the given reaction [1]:

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