<h2>Answer:</h2>
Option B is correct.
B. start a chemical reaction
<h2>
Explanation:</h2>
Activation energy is the amount of energy that is needed to start a chemical reaction. To start a chemical reaction we have to provide this amount of energy. Different type of catalyst are used to lower the activation energy and catalyze the reaction.
There are many factors that affect the rate of chemical reactions and temperature is one of them.
Typically, the higher the temperature of a chemical reaction the faster the reaction occur, that is, the temperature and the rate of chemical reaction are directly related. This is due to the fact that increasing the temperature of the reaction increases the kinetic energy of the reacting particles and thus they are able to move faster and the reaction also occur faster. Thus, from the options given, the correct answer will be D [40 degree], this is because, it is the highest temperature out of all the options given.
The second one should be the answer not 100% but like 85% sure
Answer:
1. Sorting. The simplest way to separate mechanical mixtures is by sorting.
2. Floating. Sometimes, parts of a mechanical mixture will float on the surface.
3. Settling. Sand and cocoa powder both settle in water.
4. Using a Magnet. Some metals such as iron and steel are attracted to magnets.
5. Using Sieves and Filters.
6. Dissolving.
Explanation:
Mixtures can be separated using a variety of techniques.
Chromatography involves solvent separation on a solid medium.
Distillation takes advantage of differences in boiling points.
Evaporation removes a liquid from a solution to leave a solid material.
Filtration separates solids of different sizes.
Please mark me as Brainliest. Thank you!
