CHEMISTRY UNIT 3
A 150 mL sample of hydrochloric acid (HCl) completely reacted with 60.0 mL of a 0.100 M NaOH solution. The equation for the reaction is given below. HCl + NaOH mc011-1.jpg NaCl + H2O What was the original concentration of the HCl solution? 0.040 M 0.25 M 1.50 M 2.50 M
A 0.040 M
A chemistry teacher adds 50.0 mL of 1.50 M H2SO4 solution to 200 mL of water. What is the concentration of the final solution? Use mc017-1.jpg. 0.300 M 0.375 M 6.00 M 7.50 M
A 0.300 M
A student was comparing the solubility of equal amounts of table salt and table sugar at different temperatures.The table below shows the four samples that the student used and the temperature of the water that they were dissolved in. Sample Name Chemical formula Temperature of water (°C) 1 Table sugar C12H22O11 80 2 Table sugar C12H22O11 45 3 Table salt NaCl 55 4 Table salt NaCl 63 Which of the samples most likely had the highest solubility? 1 2 3 4
A 1
A 1-L soda bottle contains dissolved carbon dioxide gas. Which bottle would have the highest concentration of dissolved gas? a bottle that is sealed a bottle that was opened 1 minute ago a bottle that was opened 1 hour ago a bottle that was opened 1 day ago
A a bottle that is sealed
What are homogeneous mixtures of metals commonly called? alloys colloids compounds suspensions
A alloys
Which is an example of a nonaqueous solution? gasoline fog mayonnaise fruit juice
A gasoline
Which method would increase the solubility of a gas? increasing the pressure stirring the solvent quickly increasing the temperature decreasing the amount of solvent
A increasing the pressure
Which factor increases the rate of dissolution in an unsaturated solution? increasing the temperature decreasing the surface area decreasing the amount of solute increasing the amount of solvent
A increasing the temperature
A chemist dissolved crystals of an unknown substance into water at room temperature. He found that 33 g of the substance can be dissolved into 100 mL of water. What property of the unknown substance was the chemist most likely investigating? its solubility its rate of dissolution its chemical reaction to water its reaction to temperature changes
A its solubility
A solution contains 90 mL of methanol, 18 mL of propanol, and 2 mL of diethyl ether. Which is the solvent in this solution? methanol propanol diethyl ether water
A methanol
Which is a way to express concentration of a solution? parts per billion moles molar mass force per square meter
A parts per billion
The molar mass of KCl is 74.55 g/mol. If 8.45 g KCl are dissolved in 0.750 L of solution, what is the molarity of the solution? Use mc030-1.jpg. 0.113 M 0.151 M 6.62 M 11.3 M
B 0.151 M
How many moles of Ba(NO3)2 are there in 0.25 L of a 2.00 M Ba(NO3)2 solution? Use mc007-1.jpg. 0.13 mol 0.50 mol 2.25 mol 8.0 mol
B 0.50 mol
A chemist dilutes a 1.0 mL sample of 2.0 M KNO3 by adding water to it. If the concentration of the solution that is obtained is 0.0080 M, what is its volume? Use mc016-1.jpg. 125 mL 250 mL 500 mL 2,000 mL
B 250 mL
Which statement best describes the formation of a solution? A large amount of solute is dissolved in a smaller amount of solvent. A small amount of solute is dissolved in a larger amount of solvent. A small amount of solvent is dissolved in a larger amount of solute. A large amount of solvent is dissolved in a larger amount of solute.
B A small amount of solute is dissolved in a larger amount of solvent.
Which is true about dissolving a polar substance in water? The solvent particles are all nonpolar molecules. The solute particles are carried into the solution. The solute particles have no attraction for the solvent molecules. The solute particles are very different from the solvent molecules.
B The solute particles are carried into the solution.
Brownian motion is not observed in a mixture that includes two phases. Which best identifies the mixture? a colloid a suspension a solution an alloy
B a suspension
Under which conditions would the solubility of a gas be greatest? high pressure and high temperature high pressure and low temperature low pressure and high temperature low pressure and low temperature
B high pressure and low temperature
Mixture A was made by mixing different components together, but it appears to have one phase. Which term best categorizes mixture A? colloid solution emulsion suspension
B solution
A nonaqueous solution has a solvent that is not water. Which is an example of a nonaqueous solution? paint steel orange juice shaving cream
B steel
Which factor influences both solubility and the rate of dissolution? pressure temperature particle size nature of solvent
B temperature
Solute crystals are added to a solution until they begin to sink to the bottom of their container. The solution is then heated, and many more solute crystals dissolve. Which term best describes the solution immediately after it was heated? saturated unsaturated concentrated supersaturated
B unsaturated
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 mc012-1.jpg Na2SO4 + 2H2O What is the concentration of NaOH that is used? 0.063 M 0.25 M 0.50 M 1.0 M
C 0.50 M
Which solution is the most concentrated? 2.0 mL of 10 M H2SO4, where H2SO4 has a molar mass of 98 g/mol 5.0 mL of 1.0 M PbSO4, where PbSO4 has a molar mass of 303 g/mol 2.0 mL of 10.5 M H2O2, where H2O2 has a molar mass of 34 g/mol 100 mL of 10 M NaCl, where NaCl has a molar mass of 58 g/mol
C 2.0 mL of 10.5 M H2O2, where H2O2 has a molar mass of 34 g/mol
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? Use mc008-1.jpg. 3.13 g 38.5 g 200 g 617 g
C 200 g
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? Use mc020-1.jpg. 3.70 mL 16.7 mL 30.0 mL 83.3 mL
C 30.0 mL
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? Use mc033-1.jpg. 0.327 M 4.29 M 6.00 M 7.35 M
C 6.00 M
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? Use mc018-1.jpg. 0.900 mL 1.11 mL 6.94 mL 7.20 mL
C 6.94 mL
The graph below shows how solubility changes with temperature. https://media.edgenuity.com/evresources/3210-06-07/mc026-1.jpg What is the solubility of Na2HAsO4 at 60°C? 20 g/100 mL of water 46 g/100 mL of water 65 g/100 mL of water 70 g/100 mL of water
C 65 g/100 mL of water
Which statement best describes a true solution? A true solution will settle out after a short period of time. A true solution coagulates when heated or boiled. A true solution will not separate in a centrifuge. A true solution has a cloudy appearance.
C A true solution will not separate in a centrifuge.
Which statement best describes the process of making a solution by diluting a stock solution? Add more solute to decrease the concentration. Add more solute to increase the concentration. Add more solvent to decrease the concentration. Add more solvent to increase the concentration.
C Add more solvent to decrease the concentration.
Which is a characteristic of a homogeneous mixture that is a liquid? It exhibits the Tyndall effect. Brownian motion is not visible in it. It cannot be separated using filtration. It has at least two phases.
C It cannot be separated using filtration.
Which is true about the dissolving process in water? Nonpolar solutes dissolve easily in water. Solute molecules surround water molecules. Molecules or ions of a solute spread throughout the water molecules. Water molecules are repelled by solute ions at the surface of the solute.
C Molecules or ions of a solute spread throughout the water molecules.
The graph below shows how solubility changes with temperature. https://media.edgenuity.com/evresources/3210-06-07/mc026-1.jpg Which two solutions have similar solubilities at 40°C? Na2SO4 and NaCl Na2HAsO4 and NaCl Na2HAsO4 and Na2SO4 Ba(NO3)2 and Ce2(SO4)3 • 9H2O
C Na2HAsO4 and Na2SO4
The water in a 150-mL flask is poured into a beaker that contains 600 mL of ethyl alcohol. Which substance is the solvent in this mixture? water because it is a very polar compound ethyl alcohol because it has a lower density than water ethyl alcohol because it has a much larger volume than water water because it has dissolved in ethyl alcohol
C ethyl alcohol because it has a much larger volume than water
Which refers to a mixture that contains more than one phase in which the characteristics of the particles vary throughout the mixture? compound element heterogeneous homogeneous
C heterogeneous
Which statement best explains the symbol [NaCl]? moles of water per liter of NaCl moles of water per liter of solution moles of NaCl per liter of solution moles of NaCl per liter of water
C moles of NaCl per liter of solution
Under which conditions will sugar most likely dissolve fastest in a cup of water? a sugar cube with stirring at 5°C a sugar cube without stirring at 15°C sugar crystals with stirring at 15°C sugar crystals without stirring at 5°C
C sugar crystals with stirring at 15°C
Given that the molar mass of NaOH is 40.00 g/mol, what mass of NaOH is needed to make 2.500 L of a 2.000 M NaOH solution? Use mc010-1.jpg. 0.1250 g 5.000 g 32.00 g 200.0 g
D 200.0 g
The graph below shows how solubility changes with temperature. https://media.edgenuity.com/evresources/3210-06-07/mc023-1.jpg How many grams of NaCl will be needed to form 600 mL of a saturated solution at 100°C? 15 g 24 g 40 g 240 g
D 240 g
Alcohol is poured into a beaker that contains 2% saltwater. Which are the solutes in the new solution? salt only alcohol only salt and water alcohol and salt
D alcohol and salt
Which of these factors will cause a solid solute to dissolve faster? increasing the air temperature increasing the amount of solute increasing the amount of solvent increasing the surface area of solute
D increasing the surface area of solute
The concentration of a solute in a solution is greater than the maximum concentration that is predicted from the solute's solubility. What is the best way to describe this solution? diluted saturated unsaturated supersaturated
D supersaturated
A can of soda contains many ingredients, including vanilla, caffeine, sugar, and water. Which ingredient is the solvent? caffeine sugar vanilla water
D water
Which statement accurately describes part of the dissolving process of a polar solute in water? Solute molecules repel water molecules. Water molecules surround solute molecules. Water molecules are strongly attracted to nonpolar substances. Solute molecules remain concentrated in one part of the solvent.
Water molecules surround solute molecules.
Milk is a heterogeneous mixture that contains different types of particles in different phases. Due to the sizes of the particles in milk and the way they are dispersed, the particles do not easily settle out. They also cannot easily be filtered out. Therefore, milk is best described as a ________
colloid
Which best defines concentration? ratio that describes the amount of solute divided by the amount of solvent or solution ratio that describes the amount of solvent or solution divided by the amount of solute ratio that describes the mass of solute divided by the mass of solvent ratio that describes the amount of solvent in a solution
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 solvent sodium nitrate, because it is the solute water, because it is the solvent water, because it is the solute
sodium nitrate, because it is the solute
Which refers to the amount of a solute that will dissolve in a given volume of solvent at a given temperature and pressure? solubility supersaturated dissolution rate concentrated
solubility
A chemist has dissolved a certain substance in water. The chemist knows that more of the substance could be dissolved into the water before it stops dissolving. Therefore, the current solution is _______.
unsaturated
