A 50.0 g solution (density = 1.12 g/mL) of potassium fluoride is placed in an evaporating...

A 50.0 g solution (density = 1.12 g/mL) of potassium fluoride is placed in an evaporating dish and the
solvent is evaporated, leaving 8.10 g of solid behind. Calculate the concentration of the solution in units of
a) mass percentage
b) molarity
c) molality

Expert Solution

given
mass of solution= 50 g
density of solution = 1.12 g/ml
mass of solute = 8.10g
mass % = mass of solute/Total mass of solution *100
= [8.10 g/50 g]*100 = 16.2 %

Answer 16.2%
**********************
volume of solution = mass/density = 50 g/1.12 g/ml
=44.643 ml = 0.044643 l

molar mass of solute KF = 58.10 g/mol

molarity = mass of solute/molar mass of solute*volume of solution in L
= 8.10 g/58.10 g/mol*0.044643 l
molarity= 3.123 M
**************************
mass of solvent = 50 g- 8.10 g= 41.9 g = 0.0419 kg
molality = mass of solute/molar mass of solute*mass of solvent in Kg
= 8.10 g/58.10 g/mol*0.0419 Kg
molality= 3.327 m
**********************

queen_honey_blossom answered 2 years ago

50.0 mL of a 0.1M fluoride solution is titrated with 0.1M calcium. Calculate the pCa at...

50.0 mL of a 0.1M fluoride solution is titrated with 0.1M calcium. Calculate the pCa at the halfway point in the titration.

(a) 3.25 M NaCl solution (density of solution = 1.08 g/mL)

Calculate the molality of each of the following aqueous solutions. (a) 3.25 M NaCl solution (density of solution = 1.08 g/mL) m (b) 51.4 percent by mass KBr solution m

The density of a 40 wt% solution of ethanol in water is 0.937 g/mL. The density...

The density of a 40 wt% solution of ethanol in water is 0.937 g/mL. The density of n-butanol is 0.810 g/mL. What is the concentration of n-butanol in ppm if you dissolve 20 μL of this alcohol in a 40 wt% solution of Ethanol in water. The final volume of the solution is 25 mL. Assume that the density of the ethanol solution does not change upon dissolution of the butanol. Use the correct number of significant figures! Hint: to...

An aqueous solution is 2.00 M urea. The density of the solution is 1.029 g/ml. What...

An aqueous solution is 2.00 M urea. The density of the solution is 1.029 g/ml. What is the molality concentration of urea in the solution?

You mix 50.0 mL of a weak monoprotic acid with 50.0 mL of NaOH solution in...

You mix 50.0 mL of a weak monoprotic acid with 50.0 mL of NaOH solution in a coffee cup calorimeter. Both solutions (and the calorimeter) were initially at 22.0C. The final temperature of the neutralization reaction was determined to be 22.5C. a) What is the total amount of heat evolved in this reaction? Show all work. b) If 0.135 moles of the monoprotic acid were neutralized in this reaction, what is the molar heat of neutralization (enthalpy) for this reaction?

A 50.0-mL solution of 0.100 M potassium hydrogen phthalate (KHP; (HP– has Ka ~ 4.0 x...

A 50.0-mL solution of 0.100 M potassium hydrogen phthalate (KHP; (HP– has Ka ~ 4.0 x 10–6 ) is titrated with 0.100 M of NaOH. Calculate the pH of the solution at various points of the titration: (a) Before 0.100 M NaOH is added; (b) After 25.0 mL of NaOH is added; (c) After 50.0 mL of NaOH is added, and (d) After 75.0 mL of NaOH is added

The pH of an aqueous solution of 0.112 M potassium fluoride, KF (aq), is ___? This...

The pH of an aqueous solution of 0.112 M potassium fluoride, KF (aq), is ___? This solution is _________acidicbasicneutral (acidic, neutral, or basic)

50.0 mL of 2.00 mol/L HNO3 solution and 50.0 mL of 1.00 mol/L NaOH solution, both...

50.0 mL of 2.00 mol/L HNO3 solution and 50.0 mL of 1.00 mol/L NaOH solution, both at 20.0 degree Celsius, were mixed in a calorimeter. Calculate the molar heat of neutralization of HNO3 in kJ/mol if: (1) final temperature was 28.9 degree Celsius; (2) the mass of the overall solution was 102.0 g; (3) the heat capacity of the calorimeter was 25.0 J/C; (4) and assume that the specific heat of solution is the same as water, 4.184 J/(g C);

A solution is prepared by mixing 50.0 mL of 0.50 M Cu(NO3)2 with 50.0 mL of...

A solution is prepared by mixing 50.0 mL of 0.50 M Cu(NO3)2 with 50.0 mL of 0.50 M Co(NO3)2. Sodium hydroxide is then added to the mixture. Assume no change in volume. Ksp = 2.2 × 10-20 for Cu(OH)2, Ksp = 1.3 × 10-15 for Co(OH)2 The hydroxide concentration at which the first metal hydroxide will just begin to precipitate is __________M Using the integer designators, the metal hydroxide that precipitates first is {(1) Cu(OH)2 or (2) Co(OH)2 } _____________M...

6. You mix 50.0 mL of a weak monoprotic acid with 50.0 mL of NaOH solution...

6. You mix 50.0 mL of a weak monoprotic acid with 50.0 mL of NaOH solution in a coffee cup calorimeter. Both solutions (and the calorimeter) were initially at 22.0OC. The final temperature of the neutralization reaction was determined to be 22.5OC. a) What is the total amount of heat evolved in this reaction? Show all work. b) If 0.135 moles of the monoprotic acid were neutralized in this reaction, what is the molar heat of neutralization (enthalpy) for this...

Question