Answer:
A. + 6.
B. + 3.
Explanation:
<em>A. K₂CrO₄:</em>
- To calculate the oxidation no. of an element in a compound:
<em>We have that the sum of the oxidation no. of different elements in the compound multiplied by its no. is equal to the overall charge of the compound.</em>
∵ 2(oxidation no. of K) + (oxidation no. of Cr) + 4(oxidation no. of O) = 0.
oxidation no. of K = + 1, oxidation no. of O = - 2.
∴ 2(+ 1) + (oxidation no. of Cr) +4(- 2) = 0.
∴ 2 + (oxidation no. of Cr) - 8 = 0.
∴ (oxidation no. of Cr) - 6 = 0.
<em>∴ oxidation no. of Cr = + 6.</em>
<em></em>
<em>B. Cr₂O₃:</em>
∵ 2(oxidation no. of Cr) + 3(oxidation no. of O) = 0.
oxidation no. of O = - 2.
∴ 2(oxidation no. of Cr) + 3(- 2) = 0.
∴ 2(oxidation no. of Cr) - 6 = 0.
∴ 2(oxidation no. of Cr) = + 6.
<em>∴ (oxidation no. of Cr) = + 6/2 = + 3.</em>
The Balanced chemical equation for above reaction will be :
The Coefficients will be :
So, Correct option is :
A. 3, 1, 1, 3
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Answer:
Molarity of NaOH solution is 1.009 M
Explanation:
Molar mass of HCl is 36.46 g/mol
Number moles = (mass)/(molar mass)
So, 0.8115 g of HCl = 
HCl = 0.02226 moles HCl
1 mol of NaOH neutralizes 1 mol of HCl.
So, if molarity of NaOH solution is S(M) then moles of NaOH required to reach endpoint is 
So, 
or, S = 1.009
So, molarity of NaOH solution is 1.009 M
Most likely decreased birth rate and increased emigration.
