What is the value of x, the acid concentration of the first solution?
A) 0.05
B) 0.10
C) 0.15
D) 0.20
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Answer:
A) 0.05
Step-by-step explanation:
Let's summarize into an equation the information we can get from that table.
We have 4 liters of an acid of an unknown concentration, let's call it (4x).
We have 10 liters of an acid with known concentration of 0.40.
And we have a total of 14 liters overall with a concentration of 0.3o.
That's like a weighted average formula: 4x + 10 y = 14z
Let's replace the concentration values we know and solve this:
4x + 10 (0.4) = 14 * 0.3
4x + 4 = 4.2
4x = 0.2
x = 0.05
So, the concentration of the 4 liters of acid on concentration X are in fact of concentration of 0.05.