Question

A stock solution was prepared by dissolving 0.593 g of pure ASA (molar mass = 180.2 g/mol) with NaOH solution and diluting with water in a 1000 mL volumetric flask. This was followed by pipetting 4.00 mL of the stock solution into flask A and 5.0 mL of the stock into flask B. Flasks A and B were each diluted to 20 mL mark of the volumetric flask. What are the concentrations, in molarity, of ASA in flasks A and B Select one:

a. 6.58 x 10-7 M and 2.22 x 10-7 M

b. 1.65 x 10-2 M and 1.32 x 10-2 M

c. 8.23 x 10-4 M and 6.58 x 10-4 M

d. 6.58 x 10-4 M and 8.23 x 10-4 M

What frequency corresponds to a wavelength of 450 nm?

Select one:

a. 6.67 x 10¹⁴ s^-1

b. 6.67 x10¹⁰ s^-1

c. 6.67 x10²⁸ s^-1

d. 6.67 x10⁵ s^-1

Answer 1

Griven stock solution preparation MasS = :5939. Molax mass = 180.99/mol Sollition Volume (u) = 1000m1 = 11 we know that molarity (M) = MASS X molay miss substitute the valles, voleme cine] M = 0·59 39 x 180.n}%mon I 11 N= 0.00329 molleit M = 0.0033 mollit A flask taken 0.0033M Solution, 4m), dilated to 20ml .: M = 0.0033 M M = ? V = HMI V = domi M, V, гу - н = 11, M, = 0.003 3M) (471) = = 0.00066M aomi Ma = 6.6x104m flask A concentration 6.6X16 HN ned with CamScanner

B Halk solution, 5ml Taken 0.00 33M Romi dilluted to / M9, = 0.0033 M V = 5 mi M = ? = com. V is r = M V mg = 6.0033 M) (5ml) = 0.000875M २om M₂ = 8.25 x 164 = 8.25x10 4 & Answer: d » 6.58X10 4ny and 8.25x10-4 wavelength 4500m freequency (u) = ç , where c = 3 Xlcºwy/s 1 (c = Velocity of 1= 4 Sonm = 4 sox loºm light) .: 9 = 3x10@mis - = 0.006666x10175 450X169m = 6.6667 1014 5 V = 6.67 x 1014 51 & Answer: A