The number of mole of lithium, Li needed for the reaction is 3.2 moles (Option D)
<h3>Balanced equation </h3>
4Li + N₂(g) → 2Li₂N
From the balanced equation above,
2 moles of Li₂N were obtained from 4 moles of Li
<h3>How to determine the mole of lithium needed </h3>
From the balanced equation above,
2 moles of Li₂N were obtained from 4 moles of Li
Therefore,
1.6 moles of Li₂N will be obtained from = (1.6 × 4) / 2 = 3.2 moles of Li
Thus, 3.2 moles of Li are needed for the reaction
Learn more about stoichiometry:
brainly.com/question/14735801
Answer:
H
Explanation:
Hydrogen is a nonmetal love:)
The ph of a saturated solution of Ca(OH)2 is 12.35
CALCULATION:
For the reaction
Ca(OH)2 → Ca2+ + 2OH-
we will use the Ksp expression to solve for the concentration [OH-] and then use the acid base concepts to get the pH:
Ksp = [Ca2+][OH-]^2
The listed Ksp value is 5.5 x 10^-6. Substituting this to the Ksp expression, we have
Ksp = 5.5 x 10^-6 = (s) (2s)^2 = 4s^3
s3 = 5.5x10^-6 / 4
Taking the cube root, we now have
s = cube root of (5.5x10^-6 / 4)s
= 0.01112
We know that the value of [OH-] is actually equal to 2s:
[OH-] = 2s = 2 * 0.01112 = 0.02224 M
We can now calculate for pOH:
pOH = - log [OH-]
= -log(0.02224)
= 1.65
Therefore, the pH is
pH = 14 - pOH
= 14 - 1.65
= 12.35
Electrons = protons
protons = atomic number
protons + neutrons = atomic mass
Therefore: a) protons + 7 = 15
protons= 15 -7
protons= 8
B) Remember proton = atomic number
so atomic number = 8
C)Now we know the atomic number so we can easily check on the periodic table what element has an atomic number of 8, which is Oxygen
