Question

QUESTION 16 What is the oxidation state of Cr in CrO42-? a. +2 b. +6 on o ou +8 ACTION 17

Answer 1

Answer 16 -

Given,

CrO42-

Oxidation state of Cr = ?

We know that,

Oxidation state of O = -2

Also,

Oxidation state of Cr + 4 * Oxidation state of O = -2

So,

Oxidation state of Cr + (4 * -2) = -2

Oxidation state of Cr = -2 + 8

Oxidation state of Cr = 6

So, OPTION B (+6) is the correct answer.

Answer 17 -

Given,

Initial Molarity of HCl = 0.100 M

Final Molarity of HCl = 1.50 M

Final Volume = 0.133 L

Initial Volume = ?

We know that,

M1V1 = M2V2

where, M1 = Initial Molarity

M2 = Final Molarity

V1 = Initial Molarity

V2 = Final Molarity

So,

Initial Volume = (M2V2) /M1

Initial Volume = (1.50 M * 0.133 L) / 0.100 M

Initial Volume = 1.995 L

So,

OPTION B (2.00 L) is the correct answer.