Question

К 190г. 10% раствора гидроксида калия добавили еще 20г.щелочи.Рассчитайте массовую долю щелочи в полученном растворе.

Answer 1

MKOH=190*0,1(10/100)=19
m2KOH=19+20=39
W=m2/M р-ра*100%=39/190*100%=20,526%~20,5%

Answer 2

Calculation of the Mass Fraction of Alkali in the Solution

To calculate the mass fraction of alkali in the solution, we need to determine the total mass of the resulting solution and the mass of the alkali added.

Given: - Initial solution: 190g of a 10% potassium hydroxide (KOH) solution. - Additional alkali added: 20g.

To calculate the mass fraction of alkali in the resulting solution, we can use the following formula:

Mass Fraction of Alkali = (Mass of Alkali / Total Mass of Solution) * 100%

Let's calculate the total mass of the resulting solution:

Total Mass of Solution = Initial Solution Mass + Mass of Alkali Added

Total Mass of Solution = 190g + 20g = 210g

Now, we can calculate the mass fraction of alkali in the resulting solution:

Mass Fraction of Alkali = (20g / 210g) * 100%

Mass Fraction of Alkali ≈ 9.52%

Therefore, the mass fraction of alkali in the resulting solution is approximately 9.52%.

Please note that the calculations are approximate due to rounding.