The answer is to your question is C.7 Hope that is right
Answer:
Any 4 characteristic of catalyst are:
1. Catalysts remain unchanged at the end of chemical reaction in their mass and structure.
2. They donot start the chemical reaction.
3. They change the rate of the chemical reaction.
4. Catalyst is specific to the chemical reaction. It means that one catalyst can alter the rate of only one chemical reaction.
The last question depends on the scientific method.
Scientific Method
1. Make an observation of what u are testing 2. Form a question about ur observations. 3. Make a hypothesis 4. Conduct your experiment 5. Record information and results.
The first question depends what you will need to use first for the experiment.
<h3><u>Answer;</u></h3>
C) A convex lens has a thick center and thin edges; a concave lens has a thin center and thicker edges.
<h3><u>Explanation;</u></h3>
- Convex lens refers to the lens which merges the light rays at a particular point, that travels through it, while a concave lens can be identified as the lens which disperses the light rays around, that hits the lenses.
- A convex lens is thicker at the center, as compared to its edges, while a concave lens is thinner at the center as compared to its edges.
- A concave lens is thicker at the edges than in the middle and spreads light rays apart producing an image smaller than the actual object. A convex lens on the other hand, is thinner at the edges and thicker towards the center, that is they are bent towards a central point.
Chlorine is a halogen and is very reactive and unstable. If released in an elemental form (Cl2), it would react with other substances immediately. However, <span>chlorofluorocarbons (CFCs) which contain chlorine are unreactive and when released they eventually end up in the upper atmosphere still "intact". In the upper atmosphere, sunlight is more intense and is able to break apart CFC, releasing the highly reactive chlorine which in turns destroys ozone which is more abundant in the upper atmosphere (stratosphere). </span>
