Question

Select all of the substances that will form electrolytes when dissolved in water?

	C12H22O11
	Na2SO4
	CH3OH
	C3H8O2
	ZnCl2 Equimolar solutions of copper(II) chloride, aluminum chloride, lithium chloride and calcium chloride are prepared. Which solution would be expected to have the highest conductivity? Hint: write the chemical formulas. a) copper(II) chloride b) aluminum chloride c) lithium chloride d) calcium chloride e) Since they are all equimolar, they would have the same conductivity

Suppose you were making 100.0 mL of a solution that is 0.040 M KCl. What mass of KCl should you weigh to make this solution?

	.30 g
	.04 g
	.004 g
	.74 g

Answer 1

Not that a substance that will conduct electricity in aqueous solution is called an electrolyte.

A strong electrolyte will conduct most of the electricity. Will typically make incandescent bulbs to light strong. This is mainly due to cations/anions in solution. Ionic compounds such as NaCl, Ba(OH)2 can form ions Na+; Ba+2 which aid in electron movement / current.

A weak electrolyte will conduct some electricity; will not make a strong incandescent bulb light. This is formed due to some ions in solution. The species, which we are analyzing, are partial soluble species. Examples are molecular samples, which will ionize partially 5-10% such as organic acids, or even salts which are not that soluble, BaCO3(s) for instance.

A non-electrolyte: These are species, which will NOT conduct electricity at all. They will form 0% of ionization. Will not turno any light on the bulb. Examples are sugar, fructose, and many other organic samples, which will not form ionization.

From the list:

C12H22O11 --> sugar, will not ionize

Na2SO4 -> strong electrolyte; Na+ ions and SO4-2 are present

CH3OH --> nonelectrolye, H+ is not likely to form in solutoion

CH3C3H8O2 --> CH3CH2CH2COOH --> ionizes partially, i.e. H+ and CH3CH2CH2COO-; this is weak electrolye

ZnCl2 -->  strong electrolyte; Zn+2 ions and Cl- are present

Q2.

Equimolar solutions of copper(II) chloride, aluminum chloride, lithium chloride and calcium chloride are prepared. Which solution would be expected to have the highest conductivity? Hint: write the chemical formulas.

CuCl2; AlCl3, LiCl, CaCl2

the mos conductivity will be formed by the solutoin with most ions in solution

from the list, AlCl3 = Al+3 and 3Cl- =total ions 1+3 = 4

this is stornger electrolyte

Q3.

Suppose you were making 100.0 mL of a solution that is 0.040 M KCl. What mass of KCl should you weigh to make this solution?

M = mol/V

mol = mass/MW

M = mass/(MW*V)

0.04 = (mass ) /(74.5513 * 0.1)

mass = 0.04 * 74.5513 *0.1

mass = 0.298 g

mass = 0.30 g