# chemistry 1st year, for midterm help

posted by on .

Hi,

Can any1 help with theses questions. I need to solve these because there will be similar questions on the midterm for me, coming week. Btw I have tried few.

1. How many milliliters of a 15.0%, by mass solution of KOH (Aq) ( d= 1.14g/mL ) are required to produce 27.0 of a solution with pH= 11.45?

Answer is required in mL. Liters is just as fine as mL :P

50.00 mL of 1.45×10−2 M HI(aq) is mixed with 85.00 mL of 1.10×10−2 M KOH (aq).
Above is the data given which is required to solve Q2:

Q2:- What is the of the final solution?

Q3:- What is the pH of an aqueous solution that is 0.124 M NH4Cl?

Thanks in Advance for answering the questions, plz provide the solution if possible?

• chemistry 1st year, for midterm help - ,

We will be happy to critique your work, or thinking. We aren't going to do your tests for you.

• chemistry 1st year, for midterm help - ,

But these questions were never taught in the class and they are appearing on the mid-term.

• chemistry 1st year, for midterm help - ,

ok, here is the thing. I have tried other questions and got the right answer :P

But for question # 2 I convert the ph to pOH and den find the OH-
den I find the # of moles from 6.8% ammonia and den I use the Kb value of ammonia to find the OH- in the 6.8% ammonia and using dat concentration I use the formula c1v1=c2v2 to get the volume which will be required to dilute the 0.625L of pH=11.65?

But I am getting an answer of 334mL which I am told is WRONG.

So plz can some1 tell me what am I missing or doing wrong.

• chemistry 1st year, for midterm help - ,

PIEASE TELL ME HOW MANY MAKES THE QUESTION