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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

Ohm
11-07-2006, 08:33 PM
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