Answer:
Bonds are broken and new bonds are formed during chemical reactions only.
Explanation:
- A physical change in a substance doesn't change what the substance is.
- In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
- Physical changes can be reversed, chemical changes cannot be reversed with the substance changed back without extraordinary means, if at all. For example, a cup of water can be frozen when cooled and then can be returned to a liquid form when heated.
So, the right choice is:
Bonds are broken and new bonds are formed during chemical reactions only.
Answer:
The dependent variable is the number of clams developing from fertilized eggs.
The independent variable is the water temperature
The optimum temperature for clam development is 30 degrees centigrade.
Explanation:
The graph of the number of clams developing from fertilized eggs and water temperature is attached to this answer.
The independent variable is being manipulated in an experiment. As it changes, it produces a corresponding change in the dependent variable.
Here, the water temperature is the independent variable. As it changes, the number of clams developing from fertilized eggs (dependent variable) also changes alongside.
The optimum temperature is the temperature at which the greatest number of clams developing from fertilized eggs is produced. We can see from the graph that this temperature is 30 degrees centigrade.
Hello!
Antifreeze says it in the name. This means that it helps prevent freezing. The liquid that would freeze if you wouldnt use the antifreeze is water. This means that the antifreeze has to have a higher freezing point then water, because otherwise it would only freeze faster!
Hope this helped you!
Incomplete question. Full question reads;
Darwin developed the theory of evolution to explain why there are so many different kinds of living things. He could easily observe that offspring of any animals were slightly different from their parents and that this could allow for big changes over thousands of years. He did not know that genes caused the differences. Genes are now very important in the modern theory of evolution.
What most likely led to a change in the widely accepted theory of evolution?
Answer:
<u>new experiments involving genes and evolution </u>
<u>Explanation:</u>
Indeed, the original theory of evolution has experienced several changes in its acceptance because of its imperfect and wrong assumptions not based on generally acceptable scientific facts,
Hence, new experiments involving genes and evolution has led to a change (disagreements and few agreements) in the widely accepted theory of evolution.
Answer:
D. The Ca[OH]2 solution may have been unsaturated
Explanation:
The solubility product constant Ksp of any given chemical compound is a term used to describe the equilibrium between a solid and the ions it contains solution. The value of the Ksp indicates the extent to which any compound can dissociate into ions in water. A higher the Ksp, implies more greater solubility of the compound in water.
If the Ksp is more than the value in literature, this false value must have arisen from the fact that the solution was unsaturated hence it appears to be more soluble than it should normally be when saturated.
