Which of the following does not change the energy of the reactants relative to the activation energy?
reducing the temperature
adding a catalyst
increasing the surface area
increasing the temperature

Option (c) is the correct answer.

Explanation:

Activation energy is defined as the minimum amount of energy required by reactants to initiate a chemical reaction.

A catalyst helps in increasing the rate of a reaction by lowering the activation energy barrier.

Whereas when we reduce the temperature then there will be decrease in energy of reactant molecules. On the other hand, increasing the temperature will increase the energy of reactants.

Increasing the surface area will not have any affect on activation energy.

Hence, we can conclude that increasing the surface area does not change the energy of the reactants relative to the activation energy.

By definition, the concentration that describes the solution is 400 .

Solute and solvent are two components of a solution. The solute is the substance (solid, liquid, or gas) that dissolves in the solvent to produce a homogeneous mixture known as a solution.

In the solution, the solute is usually found in a lower proportion than the solvent, while generally, the solvent is the component that is found in the greater proportion in the solution.

The concentration of a solution is the amount of solute (dissolved substance) in an amount of solvent or solution.

There are different ways to express the concentration of a solution.

In this case, the mass of solute per volume of solution is a measure of concentration that is determined by dividing the mass in grams of the solute present in the solution sample by the volume of the sample.

In this case, the solution contains 80 g of sugar per 200 ml (0.2 L, being 1000 mL= 1 L) of solution. Then, the mass of solute per volume of solution can be calculated as:

Solving:

Finally, the concentration that describes the solution is 400 .

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