Answer:
They reduce the bond angle to be slightly lower than the tetrahedral bond angle, approximately 104.45 degrees.
Explanation:
The unshared pair of electrons or lone pair electrons in order to have the minimum repulsion possible with each other pushes the other bonding pairs closer together making the bond angle smaller or bent.
The bond angle is slightly lower than the tetrahedral bond angle of 108 degrees, leaving the water molecule with a bent molecular geometry.
They share four electrons, two from each oxygen atom
<h3>
Answer:</h3>
42960 years
<h3>
Explanation:</h3>
<u>We are given;</u>
- Remaining mass of C-14 in a bone is 0.3125 g
- Original mass of C-14 on the bone is 80.0 g
- Half life of C-14 is 5370 years
We are required to determine the age of the bone;
- Remaining mass = Original mass × 0.5^n , where n is the number of half lives.
Therefore;
0.3125 g = 80.0 g × 0.5^n
3.90625 × 10^-3 = 0.5^n
- Introducing logarithm on both sides;
log 3.90625 × 10^-3 = n log 0.5
Solving for n
n = log 3.90625 × 10^-3 ÷ log 0.5
= 8
- Therefore, the number of half lives is 8
- But, 1 half life is 5370 years
- Therefore;
Age of the rock = 5370 years × 8
= 42960 years
Thus, the bone is 42960 years old
I think it's A but it might be different from your school and mine
