Question

.stonl sample of a 60 M solution of HCI is diluted to 200, mL A) 240 M 8) 6.0 M WI 2.10M D) 1.50 M E) 2.00 M 21) 21) Which one of the following would act like a strong electrolyte in an aqueous solution? A) NH3 B) CH3OH C) CCl4 22) 22) In which of the following pairs of ionic compounds are both chemical species soluble in water? A) Be(NO312 and Bes(PO4)2 C)Cu S and PbBr2 B) NH4F and Na(OH)2 D) K2CO3 and FeCO3 23) The passage of a solvent across a semipermeable membrane because of concentration differences is 23 called A) dialysis B) osmosisC) hydration. D) hemolysis. E) solvation. 24) Calculate the molality of the solution formed when of 500 g of glucose (Molar mass 180.2) is dissolved in 0.250 kg of water A) 0.925 molal B) 0.167 molal C) 1.11 molal D) 0.200 molal E) 0.400 molal 25) Calculate the frezing point of a 2.00 molal solution of the nonelectrolyte glucose in water. The freezing point constant for water is 1.86 °C/molal. A) -2.00 °C B) 3.72 °C C) 1.86 C D)-1.86 C E) -3.72 °C 26) How many mL of 1.24 M H2S04 reacts with 1.26 g of Al? 2AI (5)+3H2S04 (aq) -Al2(S04)3 (aq)+3 H2 (g) A) 0.565 ml B) 37.7 mL C) 22.2 mL D) 56.5 mL E) 44.8 mL hich salt is produced by the neutralization of potassium hydroxide with sulfuric acid?

Answer 1

As per the rules, only the first five questions would be answered.

1. In order to prepare a certain volume of a dilute solution from an original stock solution, we use the dilution formula which is given as:

M₁V₁ = M₂V₂

where M₁ is the concentration of the stock solution,

M₂ is the concentration of the newly prepared solution,

V₁ is the volume of the stock solution needed to prepare the new solution,

V₂ is the volume of the newly prepared solution.

Given,

M1 = 6 M

M2 = Unknown

V1 = 50 mL = 0.05 L

V2 = 200 mL = 0.2 L

Hnece using the dilution formulae we have,

M2 = M1V1 / V2

M2 = 0.05 x 6 / 0.2

= 1.50 M

$\therefore$ Molarity of the new solution = 1.50 M

Correct option is D.

21. A strong electrolyte is a substance that completely ionizes or dissociates in a solution. They mainly constitute ionic compounds since ionic compounds break completely into cations and anions. But covalent compounds do not break into ions and hence do not behave as strong electrolytes.

Among the given options, NH₃, CCl₄ and CH₃OH are covalent compounds. Only KNO₃ is ionic that dissociates completely into K⁺ and NO₃^- ions, hence behaving as a strong electrolyte.

Correct option is D.

22. Correction: NaOH and not Na(OH)₂

Of all given options, only NH₄F and NaOH forms strong bonds with water due to their ionic nature. More ionic the compound is, more it will dissociate into cations and anions and hence will be solvated more by water. However sometimes even though a compound is ionic, resulting interactions with water are not as strong due to which the solubility decreases.

Correct option is B.

23. Correct option is B.

Osmosis is defined as the flow of solvent molecules from the solvent side to the solution side that is from lower concentration region to a higher concentration region across a semi-permeable membrane.

24) Molality is given as,

Molality = Mass of solute /(Molar mass of solute x Weight of solvent in kg)

Here solute is glucose and solvent is water.

Given,

mass of glucose = 50 g

Molar mass of glucose = 180 g/mol

Mass of solvent = 0.250 kg

Putting the values in the equation for molality,

Molality = 50 / (180 x 0.250)

= 1.11 molal

Hence the correct option is C.