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MBA, Ph.D in Management
Harvard university
Feb-1997 - Aug-2003
Professor
Strayer University
Jan-2007 - Present
I already have my answers but need some verification:
1) Find the pH of solutions from the given values:
a) If [H] + = 1.25 x 10- 6, find [OH] - concentration. Remember [OH-1 ] = 1x10-14 / [H+ ]
[OH-1 ] ____________________
b) Now, find the pH of the above solution in (a)
Ans ____________________
2) Change the following pH to [H]+
a) pH 8.25
Ans _________________
b) Is it acidic, basic or neutral?
Ans. ________________________
3) Identify acid- base conjugate pair; Write acid or base on the left; conj acid or conj base on the right side on the lines below each equation.
a) H PO4-2 + HCl <===> H2 PO4-1 + Cl-
______________ _______________ _______________ ______________
b) HPO4-2 + NH3 <====> PO4-3 + NH4+
_________ ____________ _________ ____________
Which chemical specie is amphoteric ( acid and base both) ___________
4) Arrange the following acids based on Ka values, from the strongest to the weakest acid.
Acid Ka
a) HF 3.5 x 10-4
b) H2 SO4 too large
c) HCN 4.9 X 10 -10
d) H2 CO3 4.3 x 10-7
Answer ___________________________________________________________________
weakest strongst
5) Predict if each one will make a good buffer pair or not?
Why?
a) H2 BO3/ HBO3-1____________________________________________________________
b) HNO3 / NO3 -1 ______________________________________________________________
6) In question 5) above tell;
a) Which acid is the strong acid? ______________
b) Which conjugate base is stronger base ? ______________
7) Calculate the number of moles of Krypton gas that occupies a volume of 12.3 Liters at a temperature of 99.0 0 C
(change it to K ) and a pressure of 445 Torr (1 atm = 760 Torr.)
[ R = 0.0821 L, atm / mol, K]
Ans. ___________________
8) Give a mathematical expression(equations) for;
a) Charle's law _______________ b) Avagadro's Law _____________________
c) Ideal gas Law __________ d) Dalton's Law ___________________
9) A 150 ml of gas at 36.80 atm and 30.00 C (Change to Kelvin) is heated to 59.20C ( change to K) and the volume increased to 405mL. What is the new pressure?
Answer _______________________
10-a) In a mixture of helium and oxygen gases, what is the partial pressure of helium in torr , if the partial pressure of oxygen is 198 torr Hg and the total pressure of both gases is 475 torr.
Answer ______________________
10-b) What volume is occupied by 32.04 grams of CH4 at STP (1 mol = 22.4L)
Answer _____________________
11) a) Write 1 equation for each type of decay. The symbols for the three radiations below:
i) Alpha decay ____________________
ii) Beta (0-1 e) emission ____________________
iii) Positron (0+1 e) emission _______________________________
iv) Gamma Radiation _____________________________
b) i) Which one is the most penetrating ? _________________________
ii) Which one is the least penetrating ? ___________________________
12) If 100. mg of fluorine-18 is shipped at 8:00AM, the half life being 110 minutes, how much fluorine-18 is still active after 220 minutes?
Answer ___________________________
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