Question

какой объем хлороводорода нужно пропустить через раствор калий гидроксида объемом 200 мл (плотностью 1.08г (мл)) и массовой долей щелочи 10% чтобы раствор стал нейтральным? (решение и дано)

Answer 1

M(NaOH) = 200*1,08*0,1=21,6 г

21,6 г    x л
NaOH + HCl = NaCl + H2O
M=40 г/моль Vm=22,4 л/моль
n=1 моль      n=1 моль
m=40 г          V=22,4 л

x=21,6*22,4/40=12 л

Answer 2

Calculation of the Volume of Hydrochloric Acid Needed

To determine the volume of hydrochloric acid needed to neutralize the potassium hydroxide solution, we can use the equation for neutralization:

acid + base → salt + water

In this case, hydrochloric acid (HCl) is the acid, and potassium hydroxide (KOH) is the base. The balanced chemical equation for the reaction is:

HCl + KOH → KCl + H2O

According to the equation, 1 mole of HCl reacts with 1 mole of KOH to produce 1 mole of KCl and 1 mole of water.

To calculate the volume of hydrochloric acid needed, we need to determine the number of moles of potassium hydroxide present in the solution. We can use the formula:

moles = mass / molar mass

Given that the volume of the potassium hydroxide solution is 200 mL and the density of the solution is 1.08 g/mL, we can calculate the mass of the solution:

mass = volume × density

mass = 200 mL × 1.08 g/mL

Now, we need to calculate the number of moles of potassium hydroxide:

moles of KOH = mass of KOH / molar mass of KOH

The molar mass of KOH is 56.11 g/mol.

Next, we need to determine the number of moles of hydrochloric acid required to neutralize the potassium hydroxide. Since the reaction is 1:1, the number of moles of HCl will be the same as the number of moles of KOH.

Finally, we can calculate the volume of hydrochloric acid needed using the formula:

volume of HCl = moles of HCl / concentration of HCl

Given that the mass fraction of the potassium hydroxide solution is 10%, we can assume that the concentration of KOH is 10% (w/w).

Now, let's calculate the volume of hydrochloric acid needed to neutralize the potassium hydroxide solution.

Solution:

1. Calculate the mass of the potassium hydroxide solution: - Volume of the solution = 200 mL - Density of the solution = 1.08 g/mL

mass = volume × density = 200 mL × 1.08 g/mL = 216 g 2. Calculate the number of moles of potassium hydroxide: - Molar mass of KOH = 56.11 g/mol

moles of KOH = mass of KOH / molar mass of KOH = 216 g / 56.11 g/mol = 3.85 mol

3. Calculate the number of moles of hydrochloric acid required: - Since the reaction is 1:1, the number of moles of HCl will be the same as the number of moles of KOH.

moles of HCl = 3.85 mol

4. Calculate the volume of hydrochloric acid needed: - Concentration of HCl = unknown

Since the concentration of hydrochloric acid is not provided, we cannot calculate the exact volume of hydrochloric acid needed without this information.

Please provide the concentration of hydrochloric acid so that we can calculate the volume accurately.