Answer:
200 Days
Explanation:
Usually not so good in chemistry, but this is math!
Half life means in this time half goes away. What happens when two half lives pass? half of what was remaining goes away. Maybe an example will make it more clear.
Say we start with 100 grams. After the amount of time for the half life to pass completes, we have 50, or half of the original amount. The half life time passes again and THAT gets cut in half to 25 grams. this is 1/4 of the original (Hey, what we're looking for.) Just to make it clear what is happening after another half life 1/8 remains, so it goes from The starting amount to 1/2 to 1/4 to 1/8 and so on, it keeps getting cut in half.
So how many times do we have to cut 1 in half until we get to 1/4? Twice as was shown before. Now, two half lives for this element is what? 100+100 days. So 200 Days.
Bond number
The characteristic of reactions that depends on valence electrons is the bond type.
In chemistry, a chemical bond could be;
Ionic
Covalent
The type of bond formed depends on the number of valence electrons present. When there are few valence electrons on an atom, it mostly forms ionic bonds.
When there are more electrons on an atoms, it mostly forms covalent bonds and the electrons between the atoms are shared.
A neutral carbon doesn't lack any electrons. It has exactly the same number of electrons as it has neutrons.
However, it has four electrons in its outer shell in comparison with eight electrons for a noble gas.
In that sense, it needs four electrons to complete its second shell.<span />
Convection currents are caused by the movement of the magma in the mantle.
Hope This Helps You!
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