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rabiabir67

11-02-2006, 07:01 PM

a solution contains 10% of potassium ions. express the concentration in terms of mEq/l?

ans:2.56

how many millimoles of monobasic sodium phosphate is present in 100 g of the substance?

ans:725m.mol

ZnSO4 is a 2 ion electrolyte, dissociating 40% in a certain concentration. calculate dissociation constant?

<ans:1.4

HCl undergoes 80%dissociation, what will be the doissociation rate?

ans:1.8

what is the concentration in mg/ml of a solution containing 5 mEq of KCl per ml?

ans:372mg/ml

you are giving Zn Cl2 0.7% phenylephrine0.1% and boric acid 1.1% with E values 0.16, 0.32 and 0.5, the solution will be

ans: hupotonic, why, how?

a formula requires a 6 g of emulsifying agents span 90 and tween 90, required HLB is 10.5. how many gram of each emulsifying agent should be used?

ans:span 2.57 and tween3.47

the following results2,4,8,5,7,4 and standard deviation 5 what is the coeficient of variance?

ans:100

rabiabir67

11-07-2006, 07:25 PM

can anybody please help with these calculations, thankyou

try to pass

11-07-2006, 08:10 PM

Abir

you should give molecular weight

charlesjain

11-07-2006, 08:20 PM

Ques: Zinc sulfate is a two-ion electrolyte, dissociating 40% in weak solutions. Calculate its dissociation factor.

Ans: On the basis of 40% dissociation, 100 particles of zinc sulfate (ZnSO4) yield:

40 zinc ions

40 sulfate ions

60 undissociated particles

140 total particles

Because 140 particles represent 1.4 times as many particles as were present before dissociation, the dissociation factor is 1.4.

charlesjain

11-07-2006, 08:31 PM

Ques: what is the concentration in mg/ml of a solution containing 5 mEq of KCl per ml? (MOLECULAR WT. OF Kcl = 74.5)

Ans:

5mEq X 74.5

----- ----- = 372.5 mg/ml OR 0.3725 g/L

1 ml X 1 mEq

Hi Rabi

a solution contains 10% of potassium ions. express the concentration in terms of mEq/l?

ans:2.56

10 gm in 100ml

100gm- 1000ml

mEq/l = weight/ Mol.wt 100/39=2.56

molecular weitht of K is 39

how many millimoles of monobasic sodium phosphate is present in 100 g of the substance?

ans:725m.mol

Millimoles = mg/Mol.wt

but I am getting the different answer, you can check with the formaul and see.

I will try to check on other calculations as well.

Wish you all the best.

Ohm

ZnSO4 is a 2 ion electrolyte, dissociating 40% in a certain concentration. calculate dissociation constant?

<ans:1.4

HCl undergoes 80%dissociation, what will be the doissociation rate?

ans:1.8

what is the concentration in mg/ml of a solution containing 5 mEq of KCl per ml?

ans:372mg/ml

you are giving Zn Cl2 0.7% phenylephrine0.1% and boric acid 1.1% with E values 0.16, 0.32 and 0.5, the solution will be

ans: hupotonic, why, how?

a formula requires a 6 g of emulsifying agents span 90 and tween 90, required HLB is 10.5. how many gram of each emulsifying agent should be used?

ans:span 2.57 and tween3.47

the following results2,4,8,5,7,4 and standard deviation 5 what is the coeficient of variance?

ans:100[/quote]

charlesjain

11-07-2006, 08:38 PM

Ques: You are given Zn Cl2 0.7% phenylephrine0.1% and boric acid 1.1% with E values 0.16, 0.32 and 0.5, the solution will be

Ans:

(0.7x0.16) (0.1x0.32) (1.1x0.5)

-------- + -------- + -------

(100) (100) (100)

=> 0.00112+0.00032+0.0055

=> 0.00694

Isotonic Nacl (0.9%) = 0.9/100 = 0.009

Therefore: 0.009>0.00694 (Solution is Hypotonic)

charlesjain

11-07-2006, 08:50 PM

Ques: the following results2,4,8,5,7,4 and standard deviation 5 what is the coeficient of variance?

Ans:

Formula: Coeff. of variance= SD/Mean X 100

=> Mean= 2+4+8+5+7+4/6

=> Mean= 5

SD = 5

Therefore, Coeff. of variance : 5/5X100=100

fizzbizz

11-07-2006, 09:14 PM

do we need to know mol wts of molecules or is it given with the question in the exam?

charlesjain

11-07-2006, 09:19 PM

I never appeared for FPGEE but in Canadian Pharmacy Exam (PEBC), it is usally given. Otherwise, we are suppose to know some basic mol. wt. like Nacl, Kcl, Hcl, Li2Co3, Na2Co3 etc.

rabiabir67

11-09-2006, 05:58 PM

thanks to everybody specially charlesjain, you are so good i hope you luck

rabiabir67

11-11-2006, 10:28 PM

anyone can give it a try and solve the rest of these calculations