Question

К раствору азотной кислоты массой 250 г , содержащего 30% кислоты, прилили 50 г воды. Определите массовую долю кислоты в полученном растворе.

Answer 1

Ответ:

25%

Объяснение:

m₁=250 г

Δm=50 г

w₁=30% (0,3)

масса кислоты: m(HNO₃)=m₁w₁

масса нового раствора: m₂=m₁+Δm

массовая доля: w₂=m(HNO₃)/m₂=m₁w₁/(m₁+Δm)

w₂=250*0,3/(250+50)=0,25 (25%)

Answer 2

Calculating the Mass Fraction of Nitric Acid in the Solution

To determine the mass fraction of nitric acid in the solution, we can use the following formula:

Mass fraction of solute = (mass of solute / total mass of solution) × 100%

Given: - Mass of nitric acid solution = 250 g - Nitric acid concentration = 30% - Mass of water added = 50 g

First, let's calculate the mass of nitric acid in the solution.

Mass of nitric acid = (nitric acid concentration / 100) × mass of solution Mass of nitric acid = (30 / 100) × 250 g Mass of nitric acid = 0.30 × 250 g Mass of nitric acid = 75 g

Now, we can calculate the total mass of the solution.

Total mass of solution = mass of nitric acid + mass of water Total mass of solution = 75 g + 50 g Total mass of solution = 125 g

Finally, we can calculate the mass fraction of nitric acid in the solution.

Mass fraction of nitric acid = (mass of nitric acid / total mass of solution) × 100% Mass fraction of nitric acid = (75 g / 125 g) × 100% Mass fraction of nitric acid = 0.60 × 100% Mass fraction of nitric acid = 60%

Therefore, the mass fraction of nitric acid in the obtained solution is 60%.