Name:_____________________________ Period:____
Chapter 17 & 18 Worksheets
Bellwork
Chapter 17: WS #1
1. Draw three water molecules around the water molecule below. Be sure to draw them in the correct position and label at least two hydrogen bonds.
2. How much energy (in J) is required to heat 256 g of water from 20.0°C to 99.0°C?
3. How many joules are released when 24.0 g of steam at 100°C condenses to form liquid water at 0°C?
4. A 45 g piece of metal was heated to 105 °C and then dropped into a calorimeter containing 177 g of water. The temperature of the water in the calorimeter changed from 11 °C to 24.2 °C. What is the specific heat of the metal?
5. What would be some of the consequences if ice were denser than water (think of environmental effects)?
Bellwork
Chapter 17: WS #2
1. In the space below, draw molecules of water in ice crystals and molecules of water in liquid water. Use these to explain why ice has a different density than liquid water.
2. Which atom in the water molecule is most electronegative? ______________________ 3. Complete this statement and then explain it for part b.
a. Water has a ________________ vapor pressure due to ___________________.
b. _________________________________________________________________________. 4. Water has a ________________ heat capacity and a __________________ heat of vaporization. As a
direct result, coastal areas have ___________________ temperatures. 5. Hydrogen bonding causes…
Water drops to be ___________ in shape.
The vapor pressure of water to _________.
The boiling point of water to be ________.
The freezing point of water to be _______. 6. A surfactant is a substance that interferes with _________________________ and decreases the
_______________________.
7. Define and give an example of each of the following.
a. Solution – ______________________________________________________________ b. Solvent – _______________________________________________________________ c. Solute – ________________________________________________________________ d. Solvation – _____________________________________________________________
8. Below is a diagram of a salt formula unit. Draw how the salt ionizes and is surrounded by water when it dissolves.
Bellwork
Chapter 17: WS#3
1. Write the formulas for these hydrates:
a. sodium sulfate decahydrate: _______________ b. magnesium sulfate heptahydrate: ____________ c. barium hydroxide octahydrate: _____________
2. Name each hydrate:
a. SnCl4∙5H2O: __________________________ b. FeSO4∙7H2O: ______________________
-c. BaBr2∙4H2O: __________________________ d. FePO4∙4H2O: ______________________ 3. Epsom salt (MgSO4∙7H2O) changes to the monohydrate form at 150°C. Write an equation for the
change.
4. Determine the percent by mass of water in Na2SO4 ∙ 10H2O
Bellwork
Bellwork
Chapter 18: WS#1
1. In the spaces provided, write saturated, unsaturated, and supersaturated.
a. Adrian is making a solution of sodium acetate in water. He adds a little bit of the sodium acetate, stirs, and it immediately dissolves. At this point, the solution is _______________. Adrian adds more sodium acetate until it will no longer dissolve and has collected on the bottom of the beaker. This solution is ______________________. Adrian heats up the beaker and continues stirring. The leftover sodium acetate finally all dissolves. Adrian allows the solution to cool. The solution is now _________________________.
b. What would happen if Adrian added a single crystal of sodium acetate to the solution? Why?
2. What mass of AgNO3 can be dissolved in 250g of water at 20oC? (222g AgNO3 /100g H2O)
3. You are given a clear aqueous solution containing KNO3. How would you determine experimentally if the solution is unsaturated, saturated, or supersaturated?
4. Using the graph fill in the paragraph below
On the solubility chart the x-axis represents ______________ and the y-axis represents _________________________. The most soluble salt at 0.0 °C is ________, the least soluble is _______. Comparing NaCl to KCl at _____ °C NaCl becomes less soluble then KCl. One salt that is less soluble as temperature increases is ___________. At 90°C, ____ g K2Cr2O7 can be dissolved in 100 g of water. At 30°C a solution of 30g KNO3 and 100 g H2O would be________________. At 30°C a solution of 50g KNO3 and 100 g H2O would be________________.
5. If the pressure in a closed system increases, the solubility of a gas ____________. a. Fill in the gas particles in the drawing to the right that
represents this law.
6. What is the effect of pressure on the solubility of gases in liquids?
7. The solubility of methane in water at 20oC and 1.00 atm pressure is 0.026 g/L. If the temperature remains constant, what will be the solubility of this gas at the following pressures
a. 0.60 atm b. 1.80 atm
Bellwork
Chapter 18: WS #2
1. Fill in the blanks in the following table. Show your work in the blank.
2. How many mL of a 2.1 M NaOH are needed to make 311.0 mL of 0.20 M NaOH?
3. If the percent (m/v) for the solute is 14% and the volume of the solution is 250 mL, what is the mass of solute in the solution?
4. If the solubility of a gas in water is 5.0 g/L when the pressure of gas above the water is 2.7 atm, what is the pressure of the gas above the water when the solubility of the gas is 2.0 g/L?
5. Calculate the molarity of a solution that has 21.4 g of NaCl dissolved in 1200 mL of solution.
6. What is the number of moles of solute in 460 mL of a 5.0 M solution?
Moles of solute Liters of solution
Molarity
0.221 mol 1.998 L
5.48 mol 0.482 L
Bellwork
Chapter 18: WS#3
1. Solve for the molarity of the following substances.
a. 400. g CuSO4 in a 4.00 L solution b. 0.060 mol NaHCO3 in 1500 mL solution
2. You have the following stock solutions available: 2.00M NaCl, 4.0M KNO3, and 0.50M MgSO4. Calculate and describe how you would make the following solutions.
a. 500.0 mL of 0.500M NaCl b. 2.0 L of 0.20M MgSO4
c. 50.0 mL of 0.20M KNO3 d. 1.4 L of 0.500M NaCl
3. What is the concentration, in percent (m/v), of a solution with 75 g K2SO4 in 1500 mL solution?
4. Calculate the moles and grams of solute in each solution.
a. 1.0 L of 0.50M NaCl b. 5.0 X 102 mL of 2.0M KNO3
c. 250 mL of 0.10M CaCl2 d. 2.0 L of 0.30M Na2SO4
5. Magnesium metal reacts with a 65.0 ml of 1.50M zinc nitrate solution to produce the products shown below. Mg (s) + Zn(NO3)2 (aq) Mg(NO3)2 (aq) + Zn (s)
Chapter 17 and 18 Review
1. Label each substance as ionic or molecular and then as miscible or immiscible. Explain your answers in terms of polarity.
a. CH4
b. KCl
c. He
d. MgSO4
e. sucrose (C12H22O11)
f. NaHCO3
2. Circle the substances in question #2 that would be electrolytes.
3. Identify the solvent and solute in vinegar, a dilute aqueous solution of acetic acid.
a. _____ Jello
5. How many joules of heat are released when 20.0 grams of water at 80°C freeze at 0.0oC?
6. Answer the following about hydrates.
a. A crystal that loses water vapor to the air is called ___________________________________.
b. A crystal that absorbs water vapor from the air is called _______________________________.
c. What is a dessicant? (include an example)
7. Answer the following questions.
a. How many oxygen atoms are 2 formula units of Na3PO4∙7H2O? __________
b. What happens when the hydrate is heated? (write eqn) ________________________________
c. What is the name of the above hydrate? ____________________________________________
d. What is the percent of water in the above hydrate?
8. List and define the major factors that affect the rate of solution.
a. ____________---____________________________________________________ b. ____________---____________________________________________________ c. ____________---____________________________________________________
9. Sr(OH)2 has a solubility of 11.3 g/ 100 g H2O at 20.0 °C.
a. How much would be needed to make a saturated solution with 500.0 g H2O?
b. How much would be needed to make an unsaturated solution with 500.0 g H2O?
c. How much would be needed to make a supersaturated solution with 500.0 g H2O? 10. In the supersaturation lab, you created three different
solutions by changing their temperatures. Label the picture shown. (unsaturated, saturated, supersaturated)
11. Convert the values in the table on the right.
Amount of solute
Volume of solution
Molarity
4.55 mol 238 mL 2.44 g NaCl 0.0036 L
12. A student in the lab has 1.25L of a 5.00M solution of KCl.
a. How many moles and grams of KCl are present in the solution?
b. If the student adds 1.4 L of H2O what is the new molarity?
c. How many grams of KCl are in the solution from part c?
13. In the reaction to make silver nitrate (AgNO3) how many liters of 1.3 M silver (Ag) are needed to react with 5.00 L of a 12.0 M nitric acid (HNO3) solution? 3 Ag + 4 HNO3 → 3 AgNO3 + 2 H2O + NO
15. Circle the substances below that are miscible in water. Place a box around those that are miscible in gasoline.
Sugar Kerosene Olive oil Alcohol Salt
Candle wax Kool-aid powder HCl Baby oil NaOH
16. Draw a diagram of water below. Is it polar or nonpolar? What is its shape? 17. Define and give an example of the following:
a. Suspension-b.
Colloid-i. Both of these exhibit the ____________ effect. c. Brownian
motion-18. Emulsifying agents have one _____________________ and one _________________ end of the molecule. It is a colloidal dispersion of _______________ in _____________.
Examples:
19. Draw and label the heat curve diagram.
20. How many kilocalories are needed to heat a 55.8 kg block of aluminum form 250C to 950C? (specific heat of Al = 0.21 cal/goC)
Helpful information: Heat of vaporization of water: 2260 J/g Heat of fusion of water: 334 J/g
Specific heat of water: 4.18 J/g°C