Molarity

Solute, Solvent and Solution

100

Is sugar a solute, solvent or solution?

Solute

200

Is water a solute, solvent or solution?

Solvent

300

Is salt a solute, solvent or solution?

Solute

400

Is Kool Aid a solute, solvent or solution?

Solution

500

Is tea a solute, solvent or solution?

Solution

Dissolving

100

In the demo we did in class, how did iodine and hexane interact? Why

iodine dissolved in hexane because they are both non-polar. Like dissolves Like. 

200

What happens when MgCl₂ goes into water. 

It dissociates:

MgCl_2(s) -------------Mg²⁺_(aq)  +  2Cl^-_(aq)

300

Which of the following is the best solvent for dissolving Cl₂?

H₂O CO CH₄ CH₃OH

CH₄

non-polar. Like dissolves like. 

400

Which of the following is the best solvent for dissolving HCN?

C₂H₂ HF CF₄ HI

HF - is correct because polar (highest polarity)

C₂H₂ - non-polar 

CF₄ - non-polar 

HI - polar

500

Which of the following is the best solvent for dissolving CCl₄?

H₂NO_3, Ba(OH)₂,  CH₃CH₂CH₂Cl, CH₃F 

CH₃CH₂CH₂Cl -polar BUT has a 'non-polar tail'

Concentrated vs. Diluted

100

What is considered a concentrated solution?

A: A solution with a high molarity (like 2.0 M).

B: A solution with a low molarity (like 0.1 M).

A: A solution with a high molarity (like 2.0 M).

200

If the water in Ambleside has 3 mols of salt per liter of saltwater and Horseshoe Bay has 5 mols of salt per 2 liters of saltwater, which beach's water is more diluted?

Ambleside - 3 mols per litre more diluted than 2.5 moles per litre

300

How can you make a diluted solution into a concentrated solution without adding more solute? 

Remove some solvent. 

400

If we start with a 10.0 L solution of 2.0 M NaCl (salt water), and we add 10.0 L of water to it, what is the final concentration of NaCl?

1.0 M 

500

What volume of 5.0 M HCl are needed to make 2 L of a 1.0 M HCl solution?

0.4L 

Let's Talk About Molarity

100

What is the unit for molarity?

mols/liter

200

What is the molarity of a solution with 8 moles of solute and 2 liters of solution?

4 M

300

What is the molarity of a solution with 6 moles of solute, 8 liters of solvent and 9 liters of solution?

.667 M

400

Calculate the molarity of a solution containing 0.40 moles of acetic acid (CH₃COOH) in 0.250 liters of solution.

1.6 M

500

Determine the molarity of a solution containing 2.5 g of CuCl₂ in 1 L of solution.

0.0186 M

Mixing Solutions

100

When 3 moles of AlCl₃ dissolves into 1.0L of water, what will be the molarity of Al³⁺ ions?

3M

200

When 3 moles of AlCl₃ dissolves into 1.0L of water, what will be the molarity of Cl^- ions?

9M 

300

What is the concentration of the Al³⁺ ion in a solution made by mixing 1.0 L of 1.0 M AlCl₃ and 2 L of 2.0 M CaBr₂?

(hint: the compounds will all dissociate into ions, no new compounds will form) 

 

1 mol of Al in 3 L therefore [Al³⁺] is 0.67 M 

400

What is the concentration of the Ca²⁺ ion in a solution made by mixing 1.0 L of 1.0 M AlCl₃ and 2.0 L of 2.0 M CaBr₂?

(hint: the compounds will all dissociate into ions, no new compounds will form)

4 moles of Ca in 3 L of water so [Ca²⁺] is 1.3 M

500

What is the concentration of the Cl^- ions in a solution made by mixing 1.0 L of 1.0 M AlCl₃ and 2.0 L of 2.0 M CaBr₂?

(hint: the compounds will all dissociate into ions, no new compounds will form)

# of moles of Cl = 

(3 x 1)  + (2 x 4) = 11 moles in 3 L so [Cl^-] is 3.7M