I'm not totally sure. But in my view, <span>(4)a salt solution</span> would be used to prove that the gas produced by the yeast in the vacuum bottle could change the pH of the liquid in the flask
Answer:
Option (D)
Explanation:
In terms of chemistry, a catalyst is usually defined as the substance that is commonly used in a reaction in order to increase the rate of reaction, without getting consumed. It helps in the reduction of activation energy.
In the given case, the lever or a person can be considered as a catalyst because both of these will increase the efficiency (or rate) in removing the rock from the top of the perch. Thus, the lever or the human will remain the same after the removal of rock as a catalyst can be recovered after the reaction.
Therefore, the correct answer is option (D).
<span>The release of the sperm in the vagina</span>
Answer:
The tree absorbs light energy from sunlight, converting the light energy into chemical potential energy stored in chemical bonds. The tree uses this energy to build leaves and branches and fruit. When the apple hits the ground, kinetic energy is transformed into heat energy.
Explanation: