Question

The hydrogen ion concentration and pH of the solution made by mixing $ 100mL $ of $ 1.0 $ $ M $ $ HN{0_3} $ with $ 100mL $ of $ 0.8M $ $ KOH $ , are $ \_\_\_\_\_\_\_. $
 $ A) $ $ [{H^ + }] = 0.1,pH = 1 $
 $ B) $ $ [{H^ + }] = 0.01,pH = 2 $
 $ C)[{H^ + }] = 1 \times {10^{ - 12}},pH = 12 $
 $ D)[{H^ + }] = 1 \times {10^{ - 7}},pH = 7 $

Answer 1

Hint: The pH scale is logarithmic and contrarily demonstrates the grouping of hydrogen particles in the arrangement. This is on the grounds that the equation used to ascertain pH approximates.

Complete answer:
We know the formula to calculate pH $ - \log {[H]^ + } $ .
On the reaction, the neutralization will take place because $ KOH $ is a strong base and $ HN{O_3} $ is a strong base.
 $ HN{O_3} + KOH = KN{O_3} + {H_2}O $
The equivalent of base is less than that of acid that’s why, the solution will be acidic
The concentration of acid can be determined by the given molar concentration.
 $ {K_a} = \dfrac{{[KN{O_3}][{H_2}O]}}{{[HN{O_3}][KOH]}} $
= $ 0.1ml $
 $ pH = - Log{[H]^ + } $
= $ 1 $
So, the correct option is $ A) $ .

Additional Information:
A hydrogen-particle focus influences the action of compounds and consequently the microbial development rate. The ideal pH for development might be not quite the same as that for reaction. For the most part, the adequate pH range changes about the ideal by $ 1 $ to $ 2 $ pH units. Various living beings have diverse pH optima the pH ideal for some, microbes goes from pH $ 3 - 8 $ ; for yeast, pH $ 3 - 6 $ ; for molds, pH $ 3 - 7 $ ; for plant cells, pH $ 5 - 6 $ ; and for creature cells, pH $ 6.5 - 7.5 $ . Numerous living beings have components to keep up intracellular pH at a generally steady level within the sight of variances in natural pH. At the point when pH contrasts from the ideal worth, the upkeep energy necessities increment. One outcome of various pH optima is that the pH of the medium can be utilized to choose one life form over another.

Note:
The pH scale portrays the sharpness of the arrangement: acidic, impartial, or essential. A solution with a pH under $ 7 $ is an acidic, precisely $ 7 $ is a nonpartisan arrangement, or more $ 7 $ is a base. Bases have less hydrogen particles yet more hydroxide particles, addressed by the pOH or "capability of hydroxide particles.