Answer:
3 years
Explanation:
Given data:
Initial amount of sample = 160 Kg
Amount left after 12 years = 10 Kg
Half life = ?
Solution:
at time zero = 160 Kg
1st half life = 160/2 = 80 kg
2nd half life = 80/2 = 40 kg
3rd half life = 40 / 2 = 20 kg
4th half life = 20 / 2 = 10 kg
Half life:
HL = elapsed time / half life
12 years / 4 = 3 years
Hello! Let me try to answer this :)
Thanks and please correct if there are any mistakes ^ ^
<span>An exothermic reaction is one in which heat is released from the reagents into the ambient environment. Perhaps somewhat counterintuitively, condensation is in fact an example of such a reaction. During the process of the gas-to-liquid phase change, water goes from a higher-energy to lower-energy state of matter, and, as such, releases heat into the environment.</span>
2 shells because if you do the electronic configuration:
2,7 which adds up to 9
7 stands for the group it in and it also stands for how many electrons are in the outer shell.
the amount of spaces stands for which period its in therefore it in period 2
Answer:
Ash and dust fill the air and reduce sunlight.
Explanation:
Ash and dust comes out of volcanoes, and it is bad for the environment. Polluting the air and causing fogginess, it also reduces sunlight.