Chandra has 2 liters of a 14% solution of sodium hydroxide in a container. What is the amount and concentration of sodium hydroxide solution she must add to this in order to end up with 7 liters of a 34% solution?

Clearly she must add 5 liters. So, to get the concentration,

.14*2 + x*5 = .34*7

...

To solve this problem, let's break it down into steps:

Step 1: Determine the amount of sodium hydroxide in the original 2 liters of 14% solution.

To find the amount of sodium hydroxide in a solution, we multiply the volume of the solution by the concentration. In this case:
Amount of sodium hydroxide in the original solution = 2 liters * 14% = 0.28 liters

Step 2: Determine the amount of sodium hydroxide needed in the final 7 liters of 34% solution.

To find the amount of sodium hydroxide needed in the final solution, we use the equation:
Amount of sodium hydroxide needed = Total volume of solution * Desired concentration

In this case:
Amount of sodium hydroxide needed = 7 liters * 34% = 2.38 liters

Step 3: Calculate the additional amount of sodium hydroxide solution needed.

To find the additional amount of sodium hydroxide solution needed, we subtract the amount of sodium hydroxide already present in the original solution from the amount needed in the final solution.

Additional amount of sodium hydroxide solution needed = Amount of sodium hydroxide needed - Amount of sodium hydroxide in the original solution
Additional amount of sodium hydroxide solution needed = 2.38 liters - 0.28 liters = 2.1 liters

Step 4: Determine the concentration of the additional sodium hydroxide solution needed.

To find the concentration of the additional sodium hydroxide solution, we use the equation:
Concentration of additional sodium hydroxide solution = Amount of sodium hydroxide needed / Total volume of solution

In this case:
Concentration of additional sodium hydroxide solution = 2.1 liters / 7 liters = 0.3

Therefore, Chandra needs to add an additional 2.1 liters of a sodium hydroxide solution with a concentration of 0.3 in order to end up with 7 liters of a 34% sodium hydroxide solution.

To solve this problem, we need to calculate the amount and concentration of sodium hydroxide solution that Chandra must add to her existing solution.

Let's break down the problem step by step:

Step 1: Calculate the initial amount of sodium hydroxide in Chandra's 2-liter 14% solution.
To do this, we multiply the volume of the solution (2 liters) by the concentration (14% or 0.14):
Initial amount of sodium hydroxide = 2 liters * 0.14 = 0.28 liters

Step 2: Calculate the final amount of sodium hydroxide required in the 7-liter 34% solution.
To calculate the final amount of sodium hydroxide, we multiply the volume of the solution (7 liters) by the desired concentration (34% or 0.34):
Final amount of sodium hydroxide = 7 liters * 0.34 = 2.38 liters

Step 3: Calculate the additional amount of sodium hydroxide that Chandra needs to add to reach the desired amount.
To find the additional amount of sodium hydroxide, we subtract the initial amount from the final amount:
Additional amount of sodium hydroxide = Final amount - Initial amount
Additional amount of sodium hydroxide = 2.38 liters - 0.28 liters = 2.1 liters

Step 4: Calculate the concentration of the additional sodium hydroxide solution needed.
To calculate the concentration, we divide the additional amount of sodium hydroxide by the total volume of the resulting solution (7 liters):
Concentration of additional sodium hydroxide solution = Additional amount of sodium hydroxide / Total volume of resulting solution
Concentration of additional sodium hydroxide solution = 2.1 liters / 7 liters = 0.3 or 30%

Therefore, Chandra needs to add 2.1 liters of a 30% sodium hydroxide solution to her existing 2-liter 14% solution in order to end up with 7 liters of a 34% sodium hydroxide solution.