Question

К 200 г 50%-ного раствора азотной кислоты добавили 400 г 25%-ного раствора этой же кислоты.Массовая доля азотной кислоты в полученном растворе составляет...... РЕШИТЕ ПОЖАЛУЙСТА!!!

Answer 1

M(HNO3) = 200*0,5 + 400*0,25 = 200 г
m(p-pa HNO3) = 200 г + 400 г = 600 г
ω(HNO3) = 200 г/600 г = 0,3333 = 33,33%

Answer 2

Calculation of the Mass Fraction of Nitric Acid in the Solution

To calculate the mass fraction of nitric acid in the resulting solution, we need to consider the amounts and concentrations of the two solutions that were mixed.

Let's denote the following variables: - m1: mass of the first solution (200 g) - c1: concentration of the first solution (50%) - m2: mass of the second solution (400 g) - c2: concentration of the second solution (25%) - m: total mass of the resulting solution (m1 + m2)

The mass of nitric acid in the resulting solution can be calculated as follows:

mass of nitric acid = (m1 * c1) + (m2 * c2)

Now, let's substitute the given values into the equation:

mass of nitric acid = (200 g * 50%) + (400 g * 25%)

To find the mass fraction of nitric acid in the resulting solution, we divide the mass of nitric acid by the total mass of the resulting solution:

mass fraction of nitric acid = (mass of nitric acid) / (m)

Let's calculate the mass fraction of nitric acid in the resulting solution using the given values:

mass fraction of nitric acid = [(200 g * 50%) + (400 g * 25%)] / (200 g + 400 g)

Now, let's perform the calculation:

mass fraction of nitric acid = [(200 g * 0.5) + (400 g * 0.25)] / (200 g + 400 g)

mass fraction of nitric acid = (100 g + 100 g) / 600 g

mass fraction of nitric acid = 200 g / 600 g

mass fraction of nitric acid = 1/3

Therefore, the mass fraction of nitric acid in the resulting solution is 1/3 or approximately 0.333.

Please note that the calculation assumes that the concentrations given (50% and 25%) represent the mass percentages of nitric acid in the solutions.