Question

1. A student performs a reaction in a beaker by reaction silver nitrate with one long copper wire. The student’s thermometer changes from 27°C to 35°C. Based on this, is this reaction endothermic, exothermic, or neither? Explain your reasoning.

2. List three ways that the student could speed up the reaction in question 1

Answer 1

Because the thermometer isn't part of the reaction (it's outside the system), and it increases in temperature, it must be absorbing energy that was released by the chemicals. When chemicals release energy during a reaction, the reaction is exothermic.

The student could

Increase the temperature of the beaker using a hotplate/burner/stove

Increase the concentration of silver nitrate or copper wire

Cut the copper wire into smaller pieces to increase its surface area

Use a catalyst, if one exists

Answer 2

1.The reaction is exothermic .

2.

• Decrease the temperature or remove heat
• Add a catalyst
• Increase the surface area of reactants.

Step-by-step explanation:

1.

As we observed , the reading in the thermometer changes from 27°C to 35°C.

Which means, heat is released when the reaction(displacement reaction) proceeds in the forward direction. - as in to raise the temperature .

Thus it is an exothermic reaction.

2.

According to Le-Chatelier's principle ,

In a reaction , as we increase the temperature or heat , the reaction moves in the direction that consumes or uses the heat.

• Thus, an exothermic reaction moves backward when temperature is increased and moves forward as temperature is decreased.

• By adding a catalyst , the reaction happens faster because of the efficiency of catalyst.
• By increasing the surface area of the molecules, the collision between the molecules happen faster and effectively thus increasing the speed of the reaction.