Answer:
pH = 11.37
Explanation:
Sodium cyanide will dissociate into sodium ion and cyanide ion. This cyanide ion will get hydrolyzed.The ICE table for hydrolysis of cyanide ion is:
Initial 0.265 0 0
Change -x +x +x
Equilibrium 0.265-x x x
This K is Kb of HCN
Kb = Kw / Ka
Putting values
x can be ignored in denominator as Kb is very low
x= 2.33X10⁻³ M = [OH⁻]
pOH = -log[OH⁻]
pOH = -log(2.33X10⁻³ )
pOH = 2.63
pH = 14- pOH = 14-2.63 = 11.37
Answer:
1230
Explanation:
1.20×1025=1230 is your answer
Answer:
H
2
O
2
(aq)+ClO
4
−
(aq)⟶O
2
(g)+ClO
2
−
(aq)
All atoms except H and O are balanced.
The oxidation number of Cl changes from 7 to 3. The change in the oxidation number is 4.
The oxidation number of O changes from -1 to 0. The change in oxidation number per O atom is 1.
Total change in the oxidation number for 2 oxygen atoms is 2.
To balance the increase in oxidation number with decrease in the oxidation number, multiply H
2
O
2
and O
2
with coefficients 2.
2H
2
O
2
(aq)+ClO
4
−
(aq)⟶2O
2
(g)+ClO
2
−
(aq)
To balance O atoms, add 2 water molecules on RHS.
2H
2
O
2
(aq)+ClO
4
−
(aq)⟶2O
2
(g)+ClO
2
−
(aq)+2H
2
O(l)
The oxygen atoms are already balanced.
This is the balanced chemical equation
D. this is the correct answer because the question is showing a comparison of sizes rather than the actual sizes which eliminates B. A and C have no relevance.
Answer:
357.475
Explanation:
First you need periodic table and you have to look for mass
Fe = 3 x 55.845 = 167.535
P = 2 x 30.97 = 61.94
o = 4 x 2 so 8 oxygen = 8 x 16 = 128
add all and you get 357.475