Answer:
The answer is "6.52 kg and 13.1 kg"
Explanation:
For point a:
Equation:
Calculating the amount of

For point b:

Equation:
Calculating the amount of

The number of half -lives that has passed after 105 hours for krypton-79 that has half-life of 35 hours is calculated as below
if 1 half life = 35 hours
what about 105 hours = ? half-lives
= (1 half life x105 hours) /35 hours = 3 half-lives has passed after 105 hours
This question can be easily confused with. During the early times, organic compound are directly associated with living beings, people, plants and animals. That is somewhat true. The definition of organic compounds are compounds that contain carbon. So, it is true that most of the compounds in our body are organic. But you may confuse it to the abundance of elements in the body, which is oxygen. However, the most abundant element, besides carbon, in organic compounds is Hydrogen. You will notice this obviously in the organic compounds like alkanes, alkenes, alkynes, carbohydrates, lipids, hormones and proteins. Their general chemical formula usually involves Carbon and Hydrogen.
Answer:
It has to do with increasing the entropy of the universe.
Explanation:
The modern definition of entropy is that it is the extent to which a system is able to disperse its energy. Energy (such as heat!) likes to spread itself out, so that as many states as possible are occupied with the least amount of energy.
Answer:
Acid rain's effect on stone is a chemical change.
Explanation:
Acid rain has hydrochloric acid which reacts with the calcium carbonate in the stone.
I hope this helps. (Sorry if i am wrong)