Answer: Options (a) and (d) are the correct answer.
Explanation:
A catalyst is the substance which helps in increasing the rate of reaction.
Activation energy is the minimum amount of energy required by reactants to start the reaction. On addition of catalyst, the path of reaction changes because the energy barrier gap reduces and hence, the activation energy also decreases.
In the absence of catalyst, we need to increase the temperature so that reaction can occur quickly.
Whereas on addition of catalyst, there is no need to increase the temperature as the catalyst itself is sufficient to increase the rate of reaction. As a result, temperature should be lowered when there is addition of catalyst in the reaction.
Thus, we can conclude that catalysts can save money by essentially lowering the activation energy and temperature required.
Answer:
The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. The mass number is different for each different isotope of a chemical element.
B. The unknown solution had the lower concentration.
Explanation:
Osmosis is a phenomenon in which the molecules of the solvent has a tendency to move through a membrane which is semipermeable from lower concentrated side to the higher concentration side, so that the concentrations on both sides of the membrane must be equal.
So the unknown solution may have lesser concentration than the isotonic solution so that molecules of that solution move from less concentrated side to the more concentrated side, so its level drops.
Answer:
B)Continents look like they fit together
