Answer:
The first one is 425g of copper
Explanation:
B, radon is correct. Interestingly, it often collects in basements from radioactive decay of rocks such as granite that contain uranium. Because it is an unreactive noble gas and because it is denser than air it sits in basements and must be pumped out. It collects in human lungs and is the second leading cause of lung cancer behind smoking.
It is important to use low flame when evaporating water from a recovered filtrate because then the water and filtrate will not spatter and the filtrate can also be recovered after evaporating water.
If flame is not low then water as well as got spatter so it is important to use low flame so that the water and filtrate will not spatter.
Acid rain is formed by chemicals let off into the atmosphere further introducing the nitrogen oxides which are attached to the water vapour and than mixed together further making acid rain which contains a pH scale of 6 a pale light acid though very much effective.
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