Chemistry, 10.10.2019 05:00 akaeiraspruell

Use the following equilibrium reaction and constant for the deprotonation of bicarbonate (hco3-) to carbonate (co32-) to determine: hco3 = co2 + h+ k = 10-10.33 (a) whether hco3 or co32- would dominate at ph 9.1 and (b) what the concentration of [co32-] would be at this ph if [hco3 ] = 10-6 m

Answers: 3

Show answers

Answers

Answer from: Paigex3

For a: HCO_3^- will dominate at pH = 9.1

For b: The concentration of carbonate ions at pH = 9.1 will be $5.9\times 10^-8}M$

Explanation:

To calculate the pH of the solution, we use the equation:

$pH=-\log[H^+]$ ......(1)

For a:

We are given:

pH = 9.1

Putting values in equation 1, we get:

$9.1=-\log[H^+]$

$[H^+]=10^{-9.1}$

For the given chemical equation:

$HCO_3^-\rightarrow CO_3^{2-}+H^+;K_a=10^{-10.33}$

The expression of K_a for above reaction follows:

$K_a=\frac{[CO_3^{2-}]\times [H^+]}{[HCO_3^-]}$

Putting value of hydrogen ion concentration in above equation, we get:

$10^{-10.33}=\frac{[CO_3^{2-}]\times 10^{-9.1}}{[HCO_3^-]}\\\\\frac{[HCO_3^-]}{[CO_3^{2-}]}=\frac{10^{-9.1}}{10^{-10.33}}\\\\\frac{[HCO_3^-]}{[CO_3^{2-}]}=16.98$

$[HCO_3^-]=16.98\times [CO_3^{2-}]$

Hence, HCO_3^- will dominate at pH = 9.1

For b:

The expression of K_a for above reaction follows:

$K_a=\frac{[CO_3^{2-}]\times [H^+]}{[HCO_3^-]}$

We are given:

$K_a=10^{-10.33}$

$[H^+]=10^{-9.1}$

$[HCO_3^-]=10^{-6}M$

Putting values in above equation, we get:

$10^{-10.33}=\frac{[CO_3^{2-}]\times 10^{-9.1}}{10^{-6}}$

$[CO_3^{2-}]=\frac{10^{-6}\times 10^{-10.33}}{10^{-9.1}}=5.9\times 10^-8}M$

Hence, the concentration of carbonate ions at pH = 9.1 will be $5.9\times 10^-8}M$

Answer from: Quest

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form( $n_2$ ) .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

Answer from: Quest

m=9

step-by-step explanation:

7m+8=71 subtract 8 from 71 which is 63 than divide it by 7m equal 9.

Another question on Chemistry

Chemistry, 22.06.2019 07:40

21. consider the following chemical reaction: n2+ o2 2 no if 10.0 g of n2 reacts with excess oxygen then how many grams of no can be formed? a) 10.7 g b) 21.4 g c) 32.9 g d) 42.8 g page 4 of 8

Answers: 2

Answer

Chemistry, 22.06.2019 08:00

Define dew point. i am writing this part to be able to ask the question

Answers: 1

Answer

Chemistry, 22.06.2019 21:00

Which of the following is a physical property flammability heat of combustion solubility and toxicity

Answers: 1

Answer

Chemistry, 23.06.2019 01:00

Heat energy, carbon dioxide, and water are released through which process? a. photosynthesis b. depolymerization c. digestion d. cellular respiration