Answer: 120.9 grams
Explanation:
Given the question : How many grams are in 3.67 moles of Lithium cyanide?
Chemical formula of lithium cyanide = LiCN
Molar mass of LiCN: Li = 6.941 ; C = 12, N = 14
LiCN = (6.941 + 12 + 14). = 32.941 g/mol
(Gram of substance / mole of substance) = (molar mass of substance / one mole)
(Gram of substance / 3.67) = (32.941 / 1)
= gram * 1 = 3.67 * 32.941
Gram of substance = 120.89347
= 120.9 grams
Answer:
c) a buffer solution with pH= 5
Explanation:
The equation of hydrolisis of water is:
1x10⁻¹⁴ = [H⁺] [OH⁻]
That means if we know [H⁺] we can find hydroxide-ion concentration and vice versa.
a) HCl 0.1M = [H⁺] = 0.1M;
1x10⁻¹⁴ / [H⁺]
1x10⁻¹⁴/ 0.1M = [OH⁻]
1x10⁻¹³M = [OH⁻] hydroxide- ion concentration.
b) 0.1M H₂SO₄ = 0.2M [H⁺]
1x10⁻¹⁴/ 0.2M = [OH⁻]
5x10⁻¹⁴M = [OH⁻]
c) pH = 5.
[H⁺] = 1x10⁻⁵M
1x10⁻¹⁴/ 1x10⁻⁵M = [OH⁻]
1x10⁻⁹M = [OH⁻]
d) pOH = 12.
[OH⁻] = 1x10⁻¹²M
That means risht answer is:
<h3>c) a buffer solution with pH= 5</h3>
Answer:
Explanation: the module will end up working out when you mix NO2CI and CI
it has less tightly bound electrons, is able to lose electron easily as compare to metal B at it has 4 unpaired electron in 3d sub-shell.
You must remember that oxidation number of hydrogen in acids is always +1, oxidation number of oxygen in oxides & acids is always -2... metals has always oxidation number on plus!
group NO3 comes from HNO3...and oxidation number of whole acid group is always on minus and equal to the amount of hydrogen atoms in this acid... so oxidation number of NO3 = -1
we have 2 NO3 groups so 2*(-1) = -2 and that is the reason why oxidation number of Fe in this formula must be +2... because sum of all elements always gives 0!
Now we could count of oxidation number for nitrogen... we write HNO3 and start counting from right to left:
3*(-2) from oxygens + 1 from hydrogen = -5
so nitrogen must have +5 oxidation number... because sum all in formula must be 0.
