SOLUTION: a lab tech needs to make a 126-liter batch of a 20% acid solution, how can the lab tech combine a batch od an acid solution that is oure acid with another that is 10% to get desire

Question 1025825: a lab tech needs to make a 126-liter batch of a 20% acid solution, how can the lab tech combine a batch od an acid solution that is oure acid with another that is 10% to get desired concentration
Found 2 solutions by josmiceli, FrankM:
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = liters of pure acid needed
Let = liters of 10% solution needed
-----------------
(1)
(2)
-------------------------
(2)
(2)
Subtract (1) from (2)
(2)
(1)
---------------------

and

------------------
14 liters of pure acid are needed
112 liters of 10% solution are needed
---------------------------------
check:
(2)
(2)
(2)
(2)
(2)
OK
Answer by FrankM(1040) (Show Source): You can put this solution on YOUR website!
I prefer to teach this with the single variable method.
X is the amount of pure acid needed
126-X is the 10% solution needed.
You see, this eliminates the need for 2 variables, since we know they add to 126, both amounts are expressed in terms of each other.
100X+10(126-X)=20(126)
100X+1260-10X=2520
90X=1260
X=14
14 liters pure acid
112 liters 10% acid containing 11.2 liter acid.
total 25.2liters of acid in 126 liters solution is 25.2/126 = 20%
RELATED QUESTIONS
a lab tech needs to make a 60-liter batch of a 40% acid solution, how can the lab tech... (answered by ikleyn)
technician needs to make a 48 liter batch of 40% acid solution. How can the technician... (answered by josgarithmetic,MathTherapy,ikleyn)
I laboratory tech nation needs to make a 21 L batch of a 40% acid solution how can the... (answered by josmiceli)
a laboratory needs to make a 21-liter batch of a 40% acid solution. how can the... (answered by josmiceli,greenestamps)
A laboratory technician needs to make a 135-liter batch of a 20% acid solution. How can... (answered by josmiceli)
A lab tech needs to make a 10 liter batch of antiseptic that is 60% alcohol. How can she... (answered by Mathtut)
A laboratory technician needs to make a 32-liter batch of a 40% acid solution. How can... (answered by richwmiller)
A laboratory technician needs to make a 36-liter batch of a 40% acid solution. How can... (answered by josgarithmetic)
a laboratory needs to make 135 litter batch of a 20% acid solution. How can the... (answered by josmiceli)