Exploring Molarity and Solution Concentrations

This lesson covers the concepts of mixtures, solutions, and concentration, focusing on molarity as a key measure. It includes examples of calculating molarity and explores the effects of dilution. The lesson also discusses various units for solution concentration, such as mass percentage and volume percentage. Students will engage in problem-solving exercises to reinforce these concepts.

What is more common, mixtures or pure substances?

• Pure substances

• Mixtures

• Both are equally common

• Neither

What is the role of a solvent in a solution?

• It decreases the volume of the solution

• It increases the concentration of the solution

• It is the substance that dissolves the solute

• It is the substance in which the solute is dissolved

What is the most common measure of concentration in chemistry?

• Volume percentage

• Parts per million

• Mass percentage

• Molarity

How many moles of potassium iodide are in 200 milliliters of a six molar solution?

• 2.0 moles

• 1.5 moles

• 1.2 moles

• 1.0 moles

What unit conversion is necessary when dealing with milliliters in molarity calculations?

• Milliliters to kilograms

• Milliliters to grams

• Milliliters to moles

• Milliliters to liters

What is the new molarity when 500 liters of a six molar solution is diluted to two liters?

• 12.0 molar

• 6.0 molar

• 3.0 molar

• 1.5 molar

How do you calculate the volume of a new solution from a concentrated stock using dilution?

• Multiply initial volume by initial molarity

• Divide initial volume by the dilution factor

• Initial volume times initial molarity equals final volume times final molarity

• Add solvent until desired concentration is achieved

What does mass percentage represent in solution concentration?

• Volume of solute per mass of solution

• Volume of solute per volume of solution

• Mass of solute per mass of solution

• Mass of solute per volume of solution

What is the molarity of a solution if 5 milliliters of a 6.0 molar solution is diluted to 230 milliliters?

• 1.30 molar

• 0.26 molar

• 0.13 molar

• 2.60 molar

What does the volume percentage indicate in a solution?

• Volume of solvent per total volume

• Mass of solute per total mass

• Volume of solute per total volume

• Mass of solute per total volume