Podcast
Questions and Answers
What is a solution?
What is a solution?
Which expression of concentration is based on 1000 parts, mol wt per litre solvent?
Which expression of concentration is based on 1000 parts, mol wt per litre solvent?
What is the number of moles of substance in 1 Litre of solvent called?
What is the number of moles of substance in 1 Litre of solvent called?
What is a mole in chemistry used for measuring?
What is a mole in chemistry used for measuring?
Signup and view all the answers
What is the molecular weight of KCl?
What is the molecular weight of KCl?
Signup and view all the answers
Which concentration expression is based on 1000 parts, eq per liter solvent?
Which concentration expression is based on 1000 parts, eq per liter solvent?
Signup and view all the answers
How many moles are in 81.97 g of KCl?
How many moles are in 81.97 g of KCl?
Signup and view all the answers
What is the molarity of a solution containing 4 moles of HCl in 2 liters of solution?
What is the molarity of a solution containing 4 moles of HCl in 2 liters of solution?
Signup and view all the answers
How would you prepare a 0.2 M solution of NaCl using 250 mL?
How would you prepare a 0.2 M solution of NaCl using 250 mL?
Signup and view all the answers
How much of a 0.5 M solution can be made from 100 mL of 2 M solution?
How much of a 0.5 M solution can be made from 100 mL of 2 M solution?
Signup and view all the answers
Study Notes
Solutions
- A solution is a homogeneous mixture of two or more substances.
- The substance present in a larger amount is called the solvent.
- The substance present in a smaller amount is called the solute.
Concentration
- Molality expresses concentration as moles of solute per 1000 g of solvent.
- Molarity expresses concentration as moles of solute per 1000 ml (1 liter) of solution.
- Normality expresses concentration as gram equivalent weight of solute per 1000 ml (1 liter) of solution.
Moles
- A mole is a unit of measurement used in chemistry to express amounts of a chemical substance.
- One mole of a substance contains 6.022 x 10^23 particles (Avogadro's number).
Molar Mass
- The molecular weight of KCl is 74.55 g/mol (atomic weight of K + atomic weight of Cl = 39.10 g/mol + 35.45 g/mol).
Calculating Moles
- To calculate the number of moles in a given mass of a substance, divide the mass by the substance's molar mass.
- Number of moles of KCl in 81.97 g is 1.1 mol (81.97 g / 74.55 g/mol).
Molarity
- Molarity is defined as the number of moles of solute per liter of solution.
- The molarity of a solution containing 4 moles of HCl in 2 liters of solution is 2 M (4 mol / 2 L).
Preparing Solutions
- To prepare a 0.2 M solution of NaCl using 250 mL, you would dissolve 2.92 g of NaCl in 250 mL of water.
- To calculate the mass of NaCl needed, first calculate the moles of NaCl required for the solution (0.05 mol), then multiply by the molar mass of NaCl (58.44 g/mol).
Dilution
- To calculate the volume of a diluted solution, the equation M1V1 = M2V2 can be used.
- Using this equation, you can calculate that 400 mL of a 0.5 M solution can be made from 100 mL of a 2 M solution.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge of molarity, normality, solvents, solutes, and solution formation with this quiz. Learn about the concepts of mixtures, dilution, and components of solutions.
