Enabled Students investigated the reaction between a strip of zinc and excess hydrochloric acic
They monitored the volume of hydrogen produced every 15 seconds.
The conical flask was placed in a water bath at 20°C.
Students used a water bath to keep the temperature of the reaction constant.
State two other variables that should be kept the same.

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explanation:

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

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