Isotopes are atoms of the same element that have different masses. The relative atomic mass (am) is a weighted average that takes into account the abundance of each isotope. We can calculate the relative atomic mass using the following expression.

where,
- abi: percent abundance of each isotope
For Gallium,
[1]
where "x" and "y" are the unknown abundances.
We also know that the sum of both abundances must be 100%.
x + y = 100
y = 100 - x [2]
If we replace [2] in [1], we get

Then, in [2]
y = 100 - x = 100 - 20.5 = 79.5
In conclusion, Ga-69 has an abundance of 20.5% and Ga-71 has an abundance of 79.5%.
You can learn more about isotopes in: brainly.com/question/21536220?referrer=searchResults
Answer:
C) 35%
Explanation:
Thymine pairs with adenine. If thymine is 15% then so would adenine be 15%. That leaves the reaminder to be 70%. Cytosine pairs with guanine, thereby, they would each be 35%.
Answer:
Ke = 34570.707
Explanation:
- H2(g) + Br2(g) → 2 HBr(g)
equilibrium constant (Ke):
⇒ Ke = [HBr]² / [Br2] [H2]
∴ [HBr] = (37.0 mol) / (2 L) = 18.5 mol/L
∴ [Br2] = (0.110 mol) / (2 L) = 0.055 mol/L
∴ [H2] = (0.360 mol) / (2 L) = 0.18 mol/L
⇒ Ke = (18.5 mol/L)² / (0.055 mol/L)(0.18 mol/L)
⇒ Ke = 34570.707
Answer:
water was added to powdered rock
Explanation: