Question

A lab technician needs to make 60 mL of 32% nitric acid solution. The acid solutions available are 20% nitric acid solution and 40% nitric acid solution. How many millilitres of each solution should be mixed to make the 32% solution?

Answer 1

if you have 20% of nitric acid...how many % of non-nitric do you add?

Answer 2

i think there is mistake in the question @genius12 since here you have writen 20 nitric acid soln and 40% nitric acid soln , they are both same , can we write it as 60% nitric acid soln ? may be i am wrong

Answer 3

No the question is exactly what I typed

Answer 4

But you might be right, I at first thought that there is something wrong with the question. But maybe there isn't?

Answer 5

what doyou mean @mathslover ?

Answer 6

@lgbasallote i meant that in the 2nd line it is written 20% nitric acid soln and 40% nitric acid soln why is there nitrc acid written two times ? i mean that can it be written as 60% ntric acid soln as a whole

Answer 7

@genius12 like i was saying...if you have 20% nitric acid...how much percent of non-nitric acid do you have?

Answer 8

good going @lgbasallote carry on

Answer 9

12%?

Answer 10

what's 100% - 20%?

Answer 11

are you there @genius12 ?

Answer 12

yes i am

Answer 13

oh 80%

Answer 14

are you there @Igbasallote

Answer 15

are you there @lgbasallote

Answer 16

80% is right...what about for 40%?

Answer 17

60%

Answer 18

and 32%?

Answer 19

68%

Answer 20

good...so you have x mL of 20% nitric acid added to y mL of 40% nitric acid and this results to 60 mL of 32% nitric acid...agree?

Answer 21

yes

Answer 22

good...so can you set up the equation for the non-nitric acid?

Answer 23

no

Answer 24

why not?

Answer 25

I don't feel confident

Answer 26

lol that's fine

Answer 27

just try

Answer 28

plz no

Answer 29

I tried, I know it's easy, and that's what is hard for me -.-

Answer 30

fine..i'll guide you..what is the measurement of the 20% nitric acid? i mean how many mL is it?

Answer 31

I do not know, I haven't found that out

Answer 32

what did i write?

Answer 33

measurement of the 20% nitric acid, in mL

Answer 34

i meant how many mL of 20% did i write?

Answer 35

you didn't

Answer 36

i wrote something...check it again

Answer 37

you did write, but not the mL

Answer 38

look at what i wrote again "good...so you have x mL of 20% nitric acid added to y mL of 40% nitric acid and this results to 60 mL of 32% nitric acid...agree?"

Answer 39

so x + y = 60
and 0.2x + 0.4y = 0.32
Is that correct, and is that what you mean?

Answer 40

no...im just asking how many mL did i say 20% of nitric acid have

Answer 41

80%? You didn't say anything for mL

Answer 42

80% is not mL

don't think about numbers...just look at what i said

Answer 43

i didnt say a value yet but i did assign a letter

Answer 44

you said 'x' mL of 20% and 'y' mL of 40%

Answer 45

x mL of 20% <--that's what i was asking...you have x mL...and what did you say the percent of non-nitric is when there is 20% nitric acid?

Answer 46

80%

Answer 47

therefore you have x mL of 80% NON nitric acid..got it?

Answer 48

ya, and y mL of 60% non-nitric acid for other solution

Answer 49

you got it

Answer 50

what abt the result?

Answer 51

ummm

Answer 52

0.8x + 0.6y = 0.32(60) ???

Answer 53

no no...

Answer 54

1. dont set up the equation yet

2. remember what you were doing a while ago...you copied the mL then changed the percentage

Answer 55

I don't understand, what do u want me to do from here

Answer 56

look at what we did a while ago

x mL of 20 % nitric acid -> x mL of 80% non-nitric

y mL of 40% nitric acid -> y mL of 60% non-nitric

60 mL of 32% nitric acid -> ?

Answer 57

60 ml of 68% non-nitric acid?

Answer 58

yup

Answer 59

now we set up an equation

.20 x + .40y = 0.32(60) <---nitric equation

.80x + .60y = 0.68(60) <---non-nitric

Answer 60

do you understand that?

Answer 61

yes

Answer 62

now I can solve the linear system for x and y?

Answer 63

good..now simplify it

Answer 64

now I can solve the linear system for x and y?

Answer 65

yup

Answer 66

k ty, my brain is merely working. I am screwing up easy questions and its 1:40 am -.-

Answer 67

it's not simple actually...it needs outside the box thinking lol

Answer 68

well I thought it was simple. But ty for help. =)