Chemistry Unit 5: The Dynamics of Chemical Reactions and Ocean Acidification Lesson 4

Which solution is the most concentrated?

2.0 mL of 10.5 M H2O2, where H2O2 has a molar mass of 34 g/mol

A student takes a measured volume of 3.00 M HCl to prepare a 50.0 mL sample of 1.80 M HCl. What volume of 3.00 M HCl did the student use to make the sample?

30.0 mL

In a school's laboratory, students require 50.0 mL of 2.50 M H2SO4 for an experiment, but the only available stock solution of the acid has a concentration of 18.0 M. What volume of the stock solution would they use to make the required solution?

6.94 mL

stock solution

a concentrated solution of a common reagent used to prepare more diluted solutions to be used in specific reactions

concentration

a ratio that describes the amount of solute divided by the amount of solvent or solution

concentrated: a solution that contains a relatively large amount of solute relative to solvent

a solution that contains a relatively large amount of solute relative to solvent

dilute

a solution that contains a relatively small amount of solute relative to solvent

Which best defines concentration?

ratio that describes the amount of solute divided by the amount of solvent or solution

Josh prepares a solution by mixing sodium nitrate and water. To calculate the molarity of the solution, Josh should calculate the moles of which substance, and why?

sodium nitrate, because it is the solute

molarity

the concentration of a solution expressed as the number of moles of solute per liter of solution

dilution

the process of adding more solvent to a solution to decrease the concentration

How would you prepare 100.0 mL of 0.400 M CaCl2 from a stock solution of 2.00 M CaCl2?

- Use the dilution equation to calculate the volume of the stock solution required. - Stock solution volume required is 20.0 mL. - Add water to concentrated solution to reach the desired volume. - The volume of water to add is 80.0 mL.

A chemist uses 0.25 L of 2.00 M H2SO4 to completely neutralize a 2.00 L of solution of NaOH. The balanced chemical equation of the reaction is given below. 2NaOH + H2SO4 Na2SO4 + 2H2O What is the concentration of NaOH that is used?

0.50 M

Rank the following coffee samples in terms of likely sweetness based on the amount of sugar added. Use 1 to indicate the sweetest coffee and 4 for the least-sweet coffee.

1 -5 g of sugar added to 50 g of coffee 2- 5 g of sugar added to 100 g of coffee 4- 2 g of sugar added to 100 g of coffee 3- 2 g of sugar added to 50 g of coffee

1. Which methods could be used to dilute a solution of sodium chloride (NaCl)? Select all that apply. 2. Label A-F based on the table using C for concentrated and D for dilute. https://media.edgenuity.com/contentengine/frames/9ecaad19-1e9f-e311-98ee-0050569c0f05/3210-06-09-10-17.jpg

1. - Add more water to the solution. - Remove a small amount of the solution and mix it with water. 2. A- B B-D C-D D-C E-D F-C

A 25 mL sample of 0.100 M HNO3 completely reacts with NaOH according to this equation: HNO3(aq) + NaOH (aq) ⟶ NaNO3(aq) + H2O(l) 1. How many moles of HNO3 are in the sample? 2. What volume of 0.0500 M NaOH solution is required to completely react with the HNO3? 3. If 0.0025 mol NaNO3 forms during the reaction, what is the concentration of NaNO3 in the final solution?

1. 0.0025 2. 50 3. 0.033

Use the periodic table in the tools bar to answer these questions. 1. How many moles of AgNO3 are present in 1.50 L of a 0.050 M solution? 2. Calculate the mass of ammonium sulfide (NH4)2S in 3.00 L of a 0.020 M solution. 3. A chemist wants a 0.100 M solution of NaOH. She has 0.0550 mol NaOH available. What volume of solution is needed to make the mixture?

1. 0.075 mol 2. 4.09 3. 0.550 L

1. How many moles of KNO3 are in 500 mL of 2.0 M KNO3? 2. How many grams of CaCl2 are in 250 mL of 2.0 M CaCl2? 3. What volume of a 6.67 M NaCl solution contains 3.12 mol NaCl?

1. 1 2. 55 3. 0.468

Find the new concentration of a solution if 25.0 mL of water is added to 125.0 mL of 0.150 M NaCl solution. 1. What is the final volume? mL 2. Which equation should you use to find the final concentration? 3. What is the new concentration? M NaCl

1. 150.0 2. A https://media.edgenuity.com/EVresources/3210-06-09-10-19-task/mc001-1.jpg 3. 0.125

Assignment Calculate the molarity of each of the following solutions. Use the periodic table if necessary. 1. A salt solution with a volume of 250 mL that contains 0.70 mol NaCl. 2. A salt solution that contains 0.90 g of NaCl in 100.0 mL of solution.

1. 2.8 2. 0.15

1. How much of a 0.250 M sucrose solution must be used to prepare 400.0 mL of a 0.0310 M solution? 2. Which statement best explains how the solution should be made? 3. What is the molarity of the solution that results when 25.0 mL of 0.513 M solution is diluted to 500.0 mL?

1. 49.6 2. Add 49.6 mL of 0.250 M sucrose to 350.4 mL of water to get 400.0 mL of 0.0310 M sucrose. 3. 0.0257

A chemical supply company sells sulfuric acid (H2SO4) in a concentration of 4.00 M. What volume of this solution would you need to make 12.0 mL of a 0.50 M H2SO4 solution? 1. Which equation should you use? 2. What is the volume needed? 3. Which statement best explains how the solution should be made?

1. A https://media.edgenuity.com/EVresources/3210-06-09-10-21-task/mc001-1.jpg 2. 1.5 3. Add 1.5 mL of 4.00 M H2SO4 to 10.5 mL of water to get 12 mL of 0.50 M H2SO4.

Warm-up 1. The molar mass of calcium chloride (CaCl2) is 110.98 g/mol. If you were to calculate the number of moles in 23.4 g of CaCl2, which example shows the correct way to set up the calculation? 2. How many moles are in 23.4 g?

1. B https://media.edgenuity.com/EVresources/3210-06-09-05-02-task/mc001-2.jpg 2. 0.211 mol CaCl2

Lesson 1. Every morning, Sarah prepares the same amount of coffee at the same temperature. Identify the coffee solution with the highest concentration. 2. Every Sunday, Sarah prepares blue fruit punch to have with dinner. Identify the fruit punch solution with the higher concentration. A science teacher adds water to a strong acid for use in the lab with students. This makes the concentration ?(3) , because the amount of solute per volume of solvent ?(4)

1. On Thursday, Sarah poured sugar into her coffee until undissolved sugar remained at the bottom of her coffee cup. 2. fruit punch with a very dark blue color 3. weaker 4. decreases

What is the molarity of a solution that contains 25 g of HCl in 150 mL of solution? (The molar mass of HCl is 36.46 g/mol.) 1. What should you find first? 2. Which setup is correct for finding moles? 3. Which setup is correct to find liters? 4. What is the molarity of this solution?

1. moles 2. B https://media.edgenuity.com/EVresources/3210-06-09-10-08-task/mc001-2.jpg 3. B https://media.edgenuity.com/EVresources/3210-06-09-10-08-task/mc002-2.jpg 4. 4.6 M HCI

Directions: Click the link here to access an interactive simulation where you will explore w hat happens when you change the concentration of different ionic compounds. Complete the steps below and answer the questions. 1. Move the shaker continuously to add cobalt (II) chloride until the concentration is 4.330 mol/L. How would you classify this solution? 2. What happened to the color of the solution as you added more of the ionic compound? 3. Tap the faucet to add another 0.5 L of water, bringing the total volume of the solution. When you doubled the water volume, what happened to the concentration? 4. How would you now classify this solution?

1. saturated 2. it got darker 3. it halved 4. unsaturated

In these solutions, identify the solute and the solvent. 1. Sea water, a solution composed of a variety of salts dissolved in water. The salt is the 2. Soda water, a solution composed of carbon dioxide gas dissolved in water. The water is the 3. Air, a solution composed of 78% nitrogen and 21% oxygen. The nitrogen is the 4. Which factors help you identify the solute and the solvent in a solution? Select all that apply.

1. solute 2. solvent 3. solvent 4. - In a solution, the solvent is present in a greater amount. - In a solution, the solute dissolves in a solvent.

In a group assignment, students are required to fill 10 beakers with 0.720 M CaCl2. If the molar mass of CaCl2 is 110.98 g/mol and each beaker must have 250. mL of solution, what mass of CaCl2 would be used?

200 g

What volume of a 0.100 M AgNO3 solution is required to completely react with the CaCl2 in 3.00 L of a 0.100 M CaCl2 solution? The balanced chemical equation is:

6.00 L AgNO3

A student prepares 150.0 mL of 1.40 M HCl using 35.0 mL of a stock solution. What is the concentration of the stock solution?

6.00 M

Which equation shows the proper setup to find the volume of a 0.250 M CaCl2 solution that contains 39.5 g of CaCl2?

b https://media.edgenuity.com/EVresources/3210-06-09-10-11-task/mc001-2.jpg

Which statement best explains the symbol [NaCl]?

moles of NaCl per liter of solution

Quiz Which is a way to express concentration of a solution?

parts per billion