Question

К 200г раствора сульфатной кислоты с массовой долей кислоты 9,8% добавили раствор гидроксида натрия, который содержит 16г щелочи. Вычислить массу соли, что образовалась.

Answer 1

M(H2SO4)=W(H2SO4)*m(р-ра)/100%=0,098*200=19,6г
n(H2SO4)=m/Mr=19,6г/98 г/моль=0,2 моль=1/2 n(NaOH), по уравнению:
2NaOH+H2SO4=Na2SO4+2H2O
n(NaOH)=m/Mr(NaOH)=16/40=0,4моль
 кислоты и щелочи взято в эквивалентном кол-ве
 m(Na2SO4)=n(Na2SO4)*Mr(Na2SO4)=0,2моль*(23*2+32+16*4)=0,2*142=28,4г

Answer 2

Calculation of the Mass of Salt Formed

To calculate the mass of salt formed when a solution of sodium hydroxide is added to a solution of sulfuric acid, we need to consider the balanced chemical equation for the reaction between these two compounds.

The balanced chemical equation for the reaction between sulfuric acid (H2SO4) and sodium hydroxide (NaOH) is as follows:

H2SO4 + 2NaOH → Na2SO4 + 2H2O

From the equation, we can see that one mole of sulfuric acid reacts with two moles of sodium hydroxide to form one mole of sodium sulfate and two moles of water.

To determine the mass of sodium sulfate formed, we need to know the number of moles of sulfuric acid and sodium hydroxide involved in the reaction.

Given: - Mass of sulfuric acid solution = 200 g - Mass fraction of sulfuric acid in the solution = 9.8% - Mass of sodium hydroxide added = 16 g

To calculate the number of moles of sulfuric acid, we can use the formula:

moles = mass / molar mass

The molar mass of sulfuric acid (H2SO4) is approximately 98 g/mol.

Using the given mass of sulfuric acid solution and the mass fraction of sulfuric acid, we can calculate the mass of sulfuric acid:

mass of sulfuric acid = mass of solution * mass fraction of sulfuric acid mass of sulfuric acid = 200 g * 0.098 mass of sulfuric acid = 19.6 g

Now, we can calculate the number of moles of sulfuric acid:

moles of sulfuric acid = mass of sulfuric acid / molar mass moles of sulfuric acid = 19.6 g / 98 g/mol moles of sulfuric acid = 0.2 mol

Since the balanced chemical equation shows that one mole of sulfuric acid reacts with two moles of sodium hydroxide, we can determine the number of moles of sodium hydroxide:

moles of sodium hydroxide = 2 * moles of sulfuric acid moles of sodium hydroxide = 2 * 0.2 mol moles of sodium hydroxide = 0.4 mol

Now, we can calculate the molar mass of sodium sulfate (Na2SO4) to determine the mass of sodium sulfate formed:

The molar mass of sodium sulfate is approximately 142 g/mol.

mass of sodium sulfate = moles of sodium hydroxide * molar mass of sodium sulfate mass of sodium sulfate = 0.4 mol * 142 g/mol mass of sodium sulfate = 56.8 g

Therefore, the mass of sodium sulfate formed is approximately 56.8 grams.