Question

В сосуде содержится 8 литров 5%-го раствора соли. Из сосуда отлили 2 литра раствора и добавили столько же 25%-го раствора такой же соли. Вычислите концентрацию получившегося раствора. Помогите пжлст!!!!

Answer 1

8 - 2 = 6 (л) - 5%-го раствора соли осталось в сосуде.
5% = 0,05
6 * 0,05 = 0,3 - приходится на соль в остатке раствора.
25% = 0,25
2 * 0,25 = 0,5 - приходится на соль в добавленном 25%-ом растворе.
0,3 + 0,5 = 0,8 - приходится на соль в получившемся растворе.
8 : 0,8 = 10% - концентрация получившегося раствора.
Ответ: 10%.

Answer 2

Calculation of Concentration of the Solution

To calculate the concentration of the resulting solution, we need to consider the initial concentration of the 8 liters of 5% salt solution and the additional 2 liters of 25% salt solution that were added.

Let's break down the calculation step by step:

1. Initial Solution: - The initial solution contains 8 liters of a 5% salt solution. - This means that in the 8 liters, there are 5% of salt and 95% of solvent (water). - To calculate the amount of salt in the initial solution, we multiply the volume (8 liters) by the concentration (5%): - Salt in the initial solution = 8 liters * 5% = 0.4 liters.

2. Added Solution: - 2 liters of a 25% salt solution were added to the initial solution. - This means that in the 2 liters, there are 25% of salt and 75% of solvent (water). - To calculate the amount of salt in the added solution, we multiply the volume (2 liters) by the concentration (25%): - Salt in the added solution = 2 liters * 25% = 0.5 liters.

3. Total Salt: - To calculate the total amount of salt in the resulting solution, we add the salt from the initial solution and the added solution: - Total salt = Salt in the initial solution + Salt in the added solution = 0.4 liters + 0.5 liters = 0.9 liters.

4. Total Volume: - To calculate the total volume of the resulting solution, we add the volume of the initial solution and the added solution: - Total volume = Volume of the initial solution + Volume of the added solution = 8 liters + 2 liters = 10 liters.

5. Concentration of the Resulting Solution: - To calculate the concentration of the resulting solution, we divide the total amount of salt by the total volume of the solution and multiply by 100 to express it as a percentage: - Concentration of the resulting solution = (Total salt / Total volume) * 100 = (0.9 liters / 10 liters) * 100 = 9%.

Therefore, the concentration of the resulting solution is 9%.

Please note that the calculations provided are based on the information given in the question.