Hey there! Here is the answer:
B.) decrease; increase
Here's why:
As you move from left to right across a period on the periodic table the size of an atom will decrease. As you move from top to bottom down a group on the periodic table the size of an atom will increase.
I really hope this answer helps you out! :)
Answer:
2.01 moles of P → 1.21×10²⁴ atoms
2.01 moles of N → 1.21×10²⁴ atoms
4.02 moles of Br → 2.42×10²⁴ atoms
Explanation:
We begin from this relation:
1 mol of PNBr₂ has 1 mol of P, 1 mol of N and 2 moles of Br
Then 2.01 moles of PNBr₂ will have:
2.01 moles of P
2.01 moles of N
4.02 moles of Br
To determine the number of atoms, we use the relation:
1 mol has NA (6.02×10²³) atoms
Then: 2.01 moles of P will have (2.01 . NA) = 1.21×10²⁴ atoms
2.01 moles of N (2.01 . NA) = 1.21×10²⁴ atoms
4.02 moles of Br (4.02 . NA) = 2.42×10²⁴ atoms
<h3><u>Answer;</u></h3>
= 11,460 years
<h3><u>Explanation;</u></h3>
- <em><u>The half life of Carbon-14 is 5,730 years
. Half life is the time taken by a radioactive material to decay by half of its original mass. Therefore, it would take a time of 5730 years for a sample of 100 g of carbon-14 to decay to 50 grams</u></em>
<em>The initial amount of carbon-14 in this case was 1 whole; thus; </em>
<em>1 → 1/2 →1/4</em>
<em>To contain 1/4 of the value, 2 half-lives have passed.
</em>
<em>But, 1 half life = 5,730 years</em>
<em>Therefore; The artifact is is therefore: 2 x 5,730
</em>
<em> = 11,460 years </em>
