Answer:
c.boron-11
Explanation:
The atomic mass of boron is 10.81 u.
And 10.81 u is a lot closer to 11u than it is to 10u, so there must be more of boron-11.
To convince you fully, we can also do a simple calculation to find the exact proportion of boron-11 using the following formula:
(10u)(x)+(11u)(1−x)100%=10.81u
Where u is the unit for atomic mass and x is the proportion of boron-10 out of the total boron abundance which is 100%.
Solving for x we get:
11u−ux=10.81u
0.19u=ux
x=0.19
1−x=0.81
And thus the abundance of boron-11 is roughly 81%.
Answer:
1.31x10⁻³ moles of H₂
Explanation:
This is the equation:
Mg(s) + 2H₂O (g) → Mg(OH)₂ (aq) + H₂(g)
Ratio is 1:1, so 1 mol of Mg is needed to produce 1 mol of H₂
Mass / Molar mass = Mol
0.032 g / 24.3 g/m = 1.31x10⁻³ moles
1.31x10⁻³ moles of H₂(g)
True when the boron control rods are lowered it slows the reaction
The H+ concentration that would best describe a basic solution would be the one having values less than 10^-7. The pH of a solution is related to H+ concentration by pH = -log[H+]. Therefore, as the concentration of H+ decreases the alkalinity would rise.
