Answer:
Option 3. The catalyst does not affect the enthalpy change (
) of a reaction.
Explanation:
As its name suggests, the enthalpy change of a reaction () is the difference between the enthalpy of the products and the reactants.
On the other hand, a catalyst speeds up a reaction because it provides an alternative reaction pathway from the reactants to the products.
In effect, a catalyst reduces the activation energy of the reaction in both directions. The reactants and products of the reaction won't change. As a result, the difference in their enthalpies won't change, either. That's the same as saying that the enthalpy change of the reaction would stay the same.
Refer to an energy profile diagram. Enthalpy change of the reaction measures the difference between the two horizontal sections. Indeed, the catalyst lowered the height of the peak. However, that did not change the height of each horizontal section or the difference between them. Hence, the enthalpy change of the reaction stayed the same.
Yes. When two things are directly prortional, that means that as one increases, the other increases at the same rate. So, say you have a 2kg object at an acceleration of 2m/s^2. The force would be 4N. If you have a 3kg object at an acceleration of 2m/s^2, the force would be 6N. If two things are inversely proportional, that means that as one thing increases the other decreases at the same rate. A good example of this is in a chemical reaction. If you increase the surface area of the reactants, the reaction time decreases. They are inversely proportional.
A homogeneous mixture is a mixture <span>which has uniform composition and properties throughout - it is identical in its every part. So, having this in mind, the correct answer is C. tap water - </span><span>even though it may have different levels of dissolved minerals and gases.</span>
What your going to do is take away the lowest number form the highest and subtract. Thats your answer...
If all the particles in a material are made up of
several smaller particles, and every larger particle
is identical, is the material a pure substance or
not? Explain your reasoning.
A pure substance is something like a compound and element. This material made of several particles which seem to be two different particles, I believe, is a mixture. So, it is not a pure substance mixtures are made up of more than one particle while compounds (In a fixed ratio, the fusion of two or more than two atoms) and elements are made up of one molecule essentially.
