Because they obtain different properties that have explosive reactions to one another
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.
I dont know the answer to this
Answer:
in a chemical reaction, the mass of the products will always be equal to the mass of the reactants.
Explanation:
The atomic number,atomic mass,valence electrons and the formula for calculating the number of neutrons is also given.The following table has been completed below in the attachment.
Explanation:
Atomic Number:the number of protons /electrons present in the nucleus of an atom is called the atomic number.
Mass Number/Atomic Mass:the number of protons and neutrons present in a nucleus
<u>Example:</u>
;here;6 implies the atomic number and 12 implies the mass number/atomic mass
<u><em>No.of neutrons=Mass number-Number of protons</em></u>
Valence electrons:the number of electrons present in the outer most shell of an atom are called valence electrons
<u>Example:</u>If we consider a carbon atom;as its <em>e</em><em>lectronic configuration is2,4 and</em> it belongs to 4th group.Therefore the number of valency electrons in carbon is <u>4.</u>