Chemistry Answers

Determine the boiling point of a 2.00 molal solution of potassium bromide, KBr. 

Calculate the molar mass of a nonelectrolyte if 40.0 grams of it dissolved in 200.0 grams of water lowers the freezing point to – 1.40 ° C.

Determine the Molarity of a solution made by dissolving 21.6 grams of sodium carbonate, Na₂CO_3, in enough water to make 400.0 ml of solution.

Calculate the pH of 0.01 M aqueous solution of sodium formate at 298 K. [Given: Ka (HCOOH) =1.7 × 10raise to the power -4 at 298K]

Calculate the degree of ionisation and the pH of a 0.01 M aqueous solution of formic acid at 298K. [Given, Ka (HCOOH) = 1.7 into 10 raise to the power -4 at 298K]. 

Calculate the pressure in a 212 Liter tank containing 23.3 kg of argon gas at 25°C? ( atomic weight Ar - 40 )

Calculate the pressure in a 212 Liter tank containing 23.3 kg of argon gas at 25°C? ( atomic weight Ar - 40 )

 Suppose the distance between two successive reflections in the optical fiber is 400μm. What is the diameter of the core of this fiber if the light is incident at 82^o at the core?

For each of these pairs of half-reactions, write a balanced equation for the overall cell reaction and calculate the standard cell potential, E^0cell.

A. Half-reactions: Cd^2+(aq) + 2e^- —> Cd(s) Cr^2+(aq) + 2e^- —> Cr(s)

Cell reaction:

E^0cell

B. Half-reactions: Fe^2+(aq) + 2e^- —> Fe(s) Br2(g) + 2e^- —> 2Br^-(aq)

Cell reaction:

E^0cell

Molar conductivity of 0.005M Kcl is 144Scm^2mol. Calculate its electrolytic conductivity in SI units (Sm^-1).