Quiz Standard 4 Answer Key - Richmond County School …



Quiz Standard 4 Answer KeyTeacher Name:Quiz Generated On: 04-29-20161)?The periodic table is organized byA)atomic mass.B)atomic size.C)atomic number.D)atomic periodicity.E)None of the aboveExplanation:The periodic table is organized by?atomic number, by the increasing number of protons in each element. This was first ordered by Russian chemist Dimitri Mendeleev.2)This section of the periodic table is called a(n)A)group.B)period.C)series.D)set.E)None of the aboveExplanation:This is a?group. The reason it is called a "group" or "family" is that they all have similar chemical characteristics, much like you and your little brother are similar, because you both have blue eyes.3)?MOST elements on the periodic table areA)gasesB)metalsC)nonmetalsD)rare earth elementsE)None of the aboveExplanation:Most elements on the periodic table are?metals. Metals have few valence electrons and dominate the entire left side of the periodic table.4)?Which type of element typically loses an electron to become an ion?A)gasB)metalC)nonmetalD)semimetalE)None of the aboveExplanation:A?metal?atom would lose an electron to become an ion. These are all located on the left of the periodic table with few valence electrons.5)Describe the location of non-metals on the periodic table?A)middleB)upper left cornerC)lower left cornerD)upper right cornerE)None of the aboveExplanation:Think about metals. Metals are typically shiny (luster) and are solid. Gases obviously do not fit this description. All the common gases are non-metals which are found in the?upper right corner.6)According to theories concerning the origin of life, the atom shown is a likely choice for the basic element of all livings things because itA)is small and unstable.B)is relatively stable and can form four covalent bonds.C)forms four ionic bonds with other elements and itself.D)is large and takes up enough space to fill the structure of a cell.E)None of the aboveExplanation:Carbon?is relatively stable and can form four covalent bonds.Carbon is an element that can form energy rich single, double or triple bonds with itself or other elements.7)?Which is a gas at room temperature?A)aluminumB)nitrogenC)potassiumD)sodiumE)None of the aboveExplanation:Nitrogen?has weak bonds with itself and is, therefore, a gas at room temperature. All of the others are to the left on the periodic table and are metals, and solids, at room temperature.8)?Which is MOST LIKELY a solid at room temperature?A)chlorineB)hydrogenC)neonD)potassiumE)None of the aboveExplanation:Potassium?is the only solid listed. All of the others are gases. If you look at the periodic table, potassium is listed on the left and is classified with all the other metals. All the rest are on the right with the nonmetals.9)The periodic table organizes elements according to INCREASINGA)atomic mass.B)energy level.C)atomic number.D)valence number.E)None of the aboveExplanation:Although there are many different organizations of the periodic table, the one that determines how elements will actually be placed is determined by the number of protons, or the?atomic number10)?Radon is the heaviest naturally radioactive ________________ gas.A)nobleB)halogenC)group 1D)diatomicE)None of the aboveExplanation:Radon is a naturally radioactive?noble?gas that is the decay product of radium. It is a danger to many low-lying basements in houses, it is chemically very stable, but highly radioactive. You can tell it is a noble gas because it is located in the eighth and last group or family of the periodic table. This tells you it has a 8 valence electrons and is very stable.11)?Elements in the same group/family of the periodic table are similar in what way?A)They are all metalsB)They are all nonmetalsC)They have a full outer shell of electrons.D)They have the same number of valence electrons.E)None of the aboveExplanation:They have the same number of valence.?This makes them similar in terms of reactability predictions and properties.12)Which of these period three elements from the periodic table would you predict to be the MOST metallic?A)AlB)ArC)ClD)SiE)None of the aboveExplanation:Al?is the most metallic element in this list. Metals are generally located on the left of the periodic table, nonmetals on the right and semi-metals on the stair step in between.13)Members of the alkaline earth elements have several things in common. They areA)nonmetals and are nonreactive.B)metals with two valence electrons.C)metals that are not very reactive.D)metalloids with two valence electrons.E)None of the aboveExplanation:The alkaline earth elements are in the same family, reactive in a like manner. They are?metals with two valence electrons; the two valence electrons helps explain why they have similar properties and react alike.14)The outlined elements have a major characteristic in common. They are allA)metals.B)nonmetals.C)very reactive.D)solids at room temperature.E)None of the aboveExplanation:These elements are all?nonmetals.?You can predict the properties of elements based on their location in the periodic table. As you move across the periodic table elements change from metals to nonmetals.15)The word?family?implies that the elements in a family have like properties. What property do the elements of the noble gas family all share?A)They are not reactive.B)They are very reactive.C)They are found in the earth's atmosphere.D)They react readily with oxygen in the air.E)None of the aboveExplanation:All of the noble gases behave alike. Because of their valence electron number?they are not reactive.?At one time, they were =called the?inert?gases because they did not react. Inert means non-reactive.16)What element behaves MOST like magnesium?A)SB)SiC)SnD)SrE)None of the aboveExplanation:Sr?behaves MOST like magnesium because it is in the same family, the alkaline earth metals. Members of the same family have the same number of valence electrons; this is an important reason why they behave alike.17)?A researcher is trying to create a new super conductive wire. Which category on the periodic table should he or she look in first?A)metalsB)non-metalsC)metalloidsD)noble gasesE)None of the aboveExplanation:Metals?are the most conductive elements because of they easily lose valence electrons. The second best would be the metalloids, with non-metals and noble gases having little ability to conduct electricity.18)?All the elements of a family in the periodic table have what feature in common?A)They all have similar chemical properties.B)They all have the same number of protons in the nucleus.C)They are all located in the same horizontal row or period.D)They all have the same number of electrons in the electron cloud.E)None of the aboveExplanation:Elements of any family in the periodic table have the same number of valence electrons. Because of this?they all have similar chemical properties.19)?The majority of elements found in the periodic table can be classified asA)gases.B)metals.C)nonmetals.D)nonreactive.E)None of the aboveExplanation:The majority of elements found in the periodic table can be classified as?metals.?Metals are found to the left of the stair-step line on the right side of the periodic table. All but one metal is solid at room temperature. Metals form positive ions because they lose electrons when forming compounds.20)An atom of an alkaline earth metal reacts with another element to form a compound. Which element MOSTLY LIKELY combined with the alkaline metal?A)ironB)neonC)oxygenD)sodiumE)None of the aboveExplanation:The alkaline earth metal has two valence electrons. So the reaction of its atom with the atom of nonmetal element with 6 valence electrons would be predicted. In this case, that would be?oxygen?.Quiz Standard 5 Answer KeyTeacher Name:Quiz Generated On: 04-29-20161)?The molecules of a substance are moving rapidly in a container. The molecules do not interact with each other. If the container is opened, the molecules will escape from the container. In what phase of matter are the molecules in the container?A)plasmaB)gasC)liquidD)solidE)None of the aboveExplanation:Based on the description, the substance must be taking the shape of its container and expanding to fill the container. The only phase of matter which does this is the?gas?phase.2)?In which state of matter has the LEAST kinetic energy?A)gasB)liquidC)plasmaD)solidE)None of the aboveExplanation:In the?solid?state has the LEAST kinetic energy. The particles in the solid state move the least, really just vibrating.3)?In which state of matter are the particles CLOSEST together?A)gasB)solidC)liquidD)plasmaE)None of the aboveExplanation:Because?solid?particles are tightly held by one another by strong attractive forces, they are most dense, and closest together. Solid water (ice) is a rare exception to this rule.4)?A sample of a substance has a high density, yet a low particle motion. This sample must be aA)gas.B)liquid.C)plasma.D)solid.E)None of the aboveExplanation:Solids?are characterized by their particles being close together, high density, and relatively little vibrational motion.5)The substances shown are ordered (from left to right) in order of increasingA)density.B)kinetic energy.C)potential energy.D)intermolecular attractions.E)None of the aboveExplanation:They are ordered by increasing?kinetic energy. Think about the motion of the particles. Ice molecules are moving slow enough that they are a solid, and steam is moving so fast it is a gas.6)Which state of matter has the greatest distance between the individual particles?A)AB)BC)CD)all are the sameE)None of the aboveExplanation:C?has the greatest distance between particles. C is steam and a gas which has the highest kinetic energy; therefore, the particles move farther apart.7)?What is going to happen to the volume of a gas that is put under MORE pressure while keeping the temperature constant?A)The volume will increase.B)The volume will decrease.C)The volume will fluctuate.D)The volume will remain constant.E)None of the aboveExplanation:The volume will decrease.?According to the gas laws, as pressure increases, the volume will decrease. There is an inverse relationship.8)?What is going to happen to a balloon filled with helium that is left in a car over night when the temperature drops approximately 20 degrees? (There are no holes in the balloon.)A)The balloon is going to pop due to the increase in volume of the gas.B)The balloon will be completely deflated due to the freezing of the gas.C)The balloon is going to look somewhat deflated due to the decrease in volume.D)Nothing, the balloon will look the same. Temperature change has no effect on gas volume.E)None of the aboveExplanation:The balloon is going to look somewhat deflated to due to the decrease in volume.?Temperature and gas volume are directly proportional, so if one decreases so does the other. But there will always be some volume so it could not have been completely deflated.9)?Why might a balloon, that is inflated almost to its capacity, pop or explode on an extremely warm day?A)The balloon may be faulty.B)It might pop because of the weakening of the balloon by the heat.C)The balloon might pop due to the increase in the volume of the gas.D)The balloon might pop because the volume will decrease within the balloon.E)None of the aboveExplanation:The balloon might pop due to the increase in the volume of the gas.?According to the gas laws; as temperature increases so does the volume of the gas.10)Which particle has the most energy?A)iceB)waterC)steamD)there is no difference in particle energyE)None of the aboveExplanation:The state of matter with most particle energy is?steam.?The faster particles move the more energy thay have, so the particles with most energy are those of the steam.11)?Tamika inflates and ties off a balloon in her classroom and then takes it outside on a cold, winter day. Immediately, she notices that the balloon has gotten a little bit smaller. Why does this occur?A)because there are fewer molecules in the balloon outsideB)because the air pressure is significantly higher when it is colderC)because the molecules in the balloon have slowed down with the temperatureD)because the molecules shrink in size when exposed to the colder, outside airE)None of the aboveExplanation:The balloon shrinks?because the molecules in the balloon have slowed down with the temperature. Once they slow down, the balloon cannot expand as much.12)?Why do the air molecules inside a bicycle tire speed up as the temperature gets warmer?A)because the heat is transferred to the molecules and gives them more kinetic energyB)because the warmer air allows the particles to be free from gravitational forcesC)because the heat liberates the potential energy inside each moleculeD)because the warmer air is less dense and particles can move moreE)None of the aboveExplanation:Air molecules speed up in warmer temperatures?because the heat is transferred to the molecules and gives them more kinetic energy. Kinetic energy is energy of motion.13)Predict the energy trend as a substance changes from a solid to liquid to gas on this graph.A)It would increase from bottom left to top right.B)It would decrease from top left to bottom right.C)It would be a horizontal line as energy would remain constant.D)It would increase from solid to liquid, then decrease from liquid to gas.E)None of the aboveExplanation:It would increase from bottom left to top right.?Energy is added to a substance as it moves from solid to liquid to gas.14)Which could complete the liquid phase description in the venn diagram?A)Definite shape and low energy particlesB)No definite shape and no definite volumeC)No definite shape and high energy particlesD)No definite shape and medium energy particlesE)None of the aboveExplanation:No definite shape and medium energy particles?would best complete the venn diagram section for a liquid.15)6 A.M. - 30 PSI9 A.M. - 32 PSI1 P.M. - 35 PSIAmy measured the tire pressure of her truck that was parked outside after a cold night. The daytime temperature reached a nice 65 °F. Assume Amy's tires do not have any leaks. Explain the change in tire pressure.A)The air molecules heated inside the tire causing them to move faster exerting more pressure on the inside walls of the tires.B)The air molecules heated inside the tire causing them to move faster exerting less pressure on the inside walls of the tires.C)The air molecules heated inside the tire causing them to move slower exerting more pressure on the inside walls of the tires.D)The air molecules heated inside the tire causing them to move slower exerting less pressure on the inside walls of the tires.E)None of the aboveExplanation:The air molecules heated inside the tire causing them to move faster exerting more pressure on the inside walls of the tires.?The greater the temperature, the faster the particles move.16)How will the behavior of the gases in the piston chamber change if more pressure is applied to the piston?A)The gas particles will slow down.B)More gas particles will be produced.C)Fewer gas particles will be produced.D)The gas particles will hit the walls more frequently.E)None of the aboveExplanation:The gas particles will hit the walls more frequently.?Because more pressure is applied, the container will shrink in size. When this happens, the particles have less space to move and will hit the walls of the container more frequently, exerting more pressure.17)How will the behavior of the gases in the piston chamber change if heat is applied to the system? Assume the piston moves to keep the pressure constant.A)The gas particles will speed up.B)More gas particles will be produced.C)Fewer gas particles will be produced.D)The kinetic energy will decrease.E)None of the aboveExplanation:The gas particles will speed up.?Because thermal energy is applied to the system, the kinetic energy of the gases increases. This results in an increase in velocity.18)Which change to the system would cause the freely-moving piston to lower?A)Apply heat to the gas particles.B)Reduce the atmospheric pressure.C)Place the system in an ice bath.D)Add more gas molecules to the system.E)None of the aboveExplanation:Place the system in an ice bath..?This would cool the particles and cause them to slow down. Then, they would exert less pressure, and the piston would fall.19)?A person opens a 2-liter bottle of cola at a picnic. If the cap is left off the bottle, the cola will become 'flat' or lose it's carbonation. Which statement below BEST summarizes why the cap must be kept tightly in place if the cola is to remain fresh?A)The cap prevents the liquid in the cola from evaporating.B)The cap keeps the atmospheric gases and liquid from mixing in the bottle.C)The cap keeps warm air from entering the two-liter bottle and raising the temperature of the cola solution.D)The cap keeps the pressure of the gas in the bottle at a high level preventing carbon dioxide from leaving the solution.E)None of the aboveExplanation:The cap keeps the pressure of the gas in the bottle at a high level preventing carbon dioxide from leaving the solution.?By keeping the pressure high, the solubility of carbon dioxide in the solution is increased.20)As matter changes state from gas to liquid, which of these statements is true?A)The particles speed up.B)The particles slow down.C)The particles get farther apart.D)The attractive force between the particles decreases.E)None of the aboveExplanation:The particles slow down as?matter changes state from a gas to a liquid. You could slow down the particles by reducing the temperature of the substance.Quiz Standard 6 Answer KeyTeacher Name:Quiz Generated On: 04-29-20161)If you wanted to design an experiment to show that the solubility of sugar in tea varies according to the temperature, what variable would remain constant?A)Volume of teaB)Concentration of teaC)Temperature of the teaD)Amount of sugar dissolvedE)None of the aboveExplanation:The?volume of tea used?must be the same in every experiment in order for the experiments to be considered valid.2)?The electrical conductivity of a substance depends on the ability of the ____ in it to move.A)electronsB)neutronsC)protonsD)quarksE)None of the aboveExplanation:The conductivity of an object depends on the ability of the?electrons?in it to move. Protons and neutrons are not involved.3)During which two minute time period is the temperature of the water changing fastest?A)0-2 minutesB)2-4 minutesC)4-6 minutesD)6-8 minutesE)None of the aboveExplanation:From?2-4 minutes?the temperature of the water is changing fastest.4)What is the independent variable in the graph?A)Degrees CB)Amount of waterC)Temperature of waterD)Time of heating the waterE)None of the aboveExplanation:Time of heating the water?is the independent variable in the graph above. This is the variable that is not being tested, the temperature of the water depends on the amount of time.5)According to the scale, which of these substances is the strongest acid?A)NaOHB)bloodC)bleachD)lemon juiceE)None of the aboveExplanation:Lemon juice/b> is the strongest acid listed. Lemon juice contains a high concentration of citric acid and has a low pH.6)?Sugar is added to tea to make sweet tea. In chemical terms the sugar is the ___________ and the tea (mostly water) is theA)endothermic, exothermic.B)chemical, dissolution.C)reactant, product.D)solute, solvent.E)None of the aboveExplanation:Solute, solvent?is correct. In solutions, a solute is what is being dissolved and a solvent is what is doing the dissolving.7)?How many variables should be manipulated in a correctly performed scientific experiment?A)oneB)threeC)twoD)zeroE)None of the aboveExplanation:In order to be a valid experiment only?one?variable should be manipulated. This ensures that the experiment will produce valuable data.8)?How does crushing a cube of solute increase the rate of dissolving?A)By increasing the amount of solvent.B)By decreasing the amount of solvent.C)By increasing the surface area of the solute.D)By decreasing the surface area of the solute.E)None of the aboveExplanation:Crushing a solute helps to increase the rate of dissolving?by increasing the surface area of the solute. If more solvent can come in contact with a greater amount of solute, the rate of dissolving increases.9)?Jake wants to quickly dissolve Gatorade in a pitcher. What would help Jake INCREASE the rate at which his Gatorade dissolves?A)adding sugarB)cooling the mixtureC)adding more GatoradeD)stirring the mixtureE)None of the aboveExplanation:Stirring the mixture?helps to expose more solute to solvent, thus increasing the rate of dissolving.10)?Which is an example of a solution?A)airB)oxygenC)saltD)waterE)None of the aboveExplanation:Air?is a solution comprised of mostly nitrogen, oxygen, carbon dioxide and water vapor. Solutions are also called homogeneous mixtures. Water is a compound and oxygen is an element, neither of which are solutions.11)?In a solution, the parts of the solution are mixedA)chemically.B)physically.C)only in water.D)by electronic means.E)None of the aboveExplanation:A solution is a?physical?combination of two or more substances. If they were chemically combined, this would be an example of a compound. Many, but not all, solutions are dissolved in water; consider air.12)?Adding powdered Gatorade to water makes a tasty solution. What is the solvent in this example?A)waterB)salt and sugarC)Gatorade liquidD)Gatorade powderE)None of the aboveExplanation:The solvent is the component that does the dissolving. In this case,?water?dissolves the Gatorade powder. Water is sometimes referred to as the universal solvent.13)?Dissolved in many gasolines are cleaning agents and anti-knock additives. These cleaning agents and additives are an example ofA)solids.B)solutes.C)solutions.D)solvents.E)None of the aboveExplanation:In this case, gasoline is the solvent and the parts added to it are the?solutes. These are the components that are dissolved.14)Based on the solubility chart, which of the listed salts is the most soluble at 25 °C?A)sodium nitrateB)sodium chlorideC)potassium nitrateD)potassium chlorateE)None of the aboveExplanation:Sodium nitrate?is the most soluble at 25 °C. Simply follow a vertical line straight up at the x-axis value of 25 until you reach the highest of the those listed in the question. Potassium iodide is much more soluble, but it is not listed as an answer choice.15)?Which statement is true about tomato juice?A)It is an acid.B)It has a pH of 7.0.C)It is strongly basic in nature.D)It is a weak hydrophobic substance.E)None of the aboveExplanation:Tomato juice?is an acid.?Tomato juice gives up H+ ions in solution, so it is considered to be an acid. It has a low pH.16)Coca cola is similar to tomato juice becauseA)they are both bases.B)they are both acids.C)they are carbonated.D)they are high in fructose.E)None of the aboveExplanation:Diet Coke and tomato juice?are both acids?because they test low on the pH scale. Solutions that have a pH below 7.0 are considered acids.17)?Which piece of lab equipment has specific markings for highly accurate measurements of liquid volumes?A)beakerB)test tubeC)watch glassD)graduated cylinderE)None of the aboveExplanation:A Graduated Cylinder.?Graduated cylinders are made to measure very specific volumes of liquid.18)The graph illustrates the?relative?activity levels of three common digestive enzymes, where 0 represents no activity and 12 represents the highest level of activity. Which enzyme is most active at a neutral pH of 7?A)pepsinB)trypsinC)amylaseD)pepsin and amaylaseE)None of the aboveExplanation:Amylase.?Amylase, found in saliva, is most active at a neutral pH of 7. This pH is too high for pepsin and too low for optimum trypsin activity.19)PepsiVinegarOrange JuiceWhat property do all three of these common household substances have in common?A)They are all acidic.B)They all taste bitter.C)They all have a pH above 7.D)They all turn litmus paper blue.E)None of the aboveExplanation:They are all acidic.?They all turn litmus paper red, have a pH below 7 and can taste sour.20)BleachDetergentAmmoniaWhat property do all three of these common household substances have in common?A)They are all acidic.B)They all taste sour.C)They all have a pH above 7.D)They all turn litmus paper red.E)None of the aboveExplanation:They all have a pH above 7.?They all turn litmus paper blue, taste bitter, and are bases.21)Lemon JuiceTums (antacid)WaterPut all of the above household items in order from lowest to highest pH.A)Lemon juice, water, TumsB)Water, Tums, Lemon JuiceC)Water, Lemon Juice, TumsD)Tums, water, lemon juiceE)None of the aboveExplanation:Lemon juice, water, Tums?is the correct order. Lemon juice is an acid with a low pH. Water has a pH of 7. And, Tums is a base with a high pH.22)What conclusion may be made based on this graph?A)Increasing temperature increases solubility.B)Decreasing temperature increases solubility.C)Increasing temperature decreases solubility.D)Increasing solubility, decreases temperature.E)None of the aboveExplanation:Increasing temperature increases solubility.?The trend for all the compounds shows a positive correlation between temperature and solubility.23)Which compound demonstrated the LEAST increase of solubility as a result of an increase in temperature?A)sodium nitrateB)sodium chlorideC)potassium iodideD)potassium nitrateE)None of the aboveExplanation:Sodium chloride?demonstrated the LEAST increase of solubility as a result in increase in temperature. It only had an increase of solubility of about 3 g/100 cm3?over a temperature increase of 100 degrees Celsius.24)Which compound demonstrated the GREATEST increase of solubility as a result of an increase in temperature?A)sodium nitrateB)sodium chlorideC)potassium nitrateD)potassium chlorateE)None of the aboveExplanation:Potassium nitrate?demonstrated the GREATEST increase of solubility as a result in increase in temperature. It had an increase of solubility of about 230 g/100 cm3?over a temperature increase of 100 degrees Celsius.25)Which solubility graph correctly depicts the increase of solubility associated with an increase of temperature of the solution?A)B)C)D)E)None of the aboveExplanation:Graph?A?demonstrates an increase of solubility as a result of increase in temperature.26)?Oven cleaner is a highly caustic chemical that reacts with baked on foods. It is dangerous to the touch and has a very slippery feel.What is the likely pH of oven cleaner?A)below 4B)around 7C)above 10D)between 5 and 7E)None of the aboveExplanation:The likely pH of oven cleaner is?above 10. Actually it can be around 13 or 14. This can be determined by the fact that it is highly caustic (corrosive) and that it feels slippery. It is a base and on the very high end of the pH scale.27)Which phrase can accurately be placed in the middle, within both circles?A)has a pH of 7B)dissolves metalsC)ionizes in waterD)turns red litmus paper blueE)None of the aboveExplanation:Ionizes in water?is the only statement that can be used to describe both acids and bases. Acids dissociate to form hydrogen (or hydronium) ions in water, bases form hydoxide ions.28)Which statement could ONLY be accurately placed within the base circle?A)is common in fruit juicesB)can be found in the stomachC)can dissolve a copper pennyD)includes many cleaners, like bleachE)None of the aboveExplanation:Only bases?include many cleaners, like bleach. Acids are found in the stomach, in fruit juices, and dissolve metals.29)BOTH acids and basesA)turn red litmus blue.B)are a component of soapsC)donate protons to solution.D)conduct electricity in water.E)None of the aboveExplanation:Both acids and bases produce ions in solution, are electrolytes, and?conduct electricity in solution.?Although red litmus is an indicator, it does not change color in an acid, acids are proton donors while bases are proton acceptors. Soaps often contain bases, not acids.30)Boiling PointElectrical conductivity in aqueous solutionSolubility in H2O (grams of solid in 100 grams H2O)ALow, 65o?CPoor3.0BHigh 1600oCGood36.0During chemistry class, Carl performed several lab tests on two white solids. The results of three tests are seen in the data table. Based on this data, Carl has concluded that substance B must have ____________ bonds.A)covalentB)diatomicC)ionicD)metallicE)None of the aboveExplanation:Based on the data, substance B must have?ionic bonds.?Ionic compounds are often soluble in water. When dissolved in water, they dissociate and form ions that conduct electricity. Finally, ionic compounds have strong intermolecular forces and therefore have a very high boiling point.31)Data AnalysisAquatic OrganismpH Range for LifeClam4.5 - 5.0Snail5.0 - 9.0Bass5.5 - 9.0Crayfish5.5 - 8.5Mayfly5.5 - 9.0Salamander6.0 - 8.0Trout6.0 - 8.5Perch6.5 - 8.5Frog7.0 - 9.5To test acidity levels of water, scientists test pH. As acid rain falls, the pH level of the water in lakes and streams decreases. While certain animals can tolerate low pH levels, others are extremely sensitive to the effects of acid rain and cannot live under these conditions. Candice is working on a project to determine whether acid rain is causing a decrease in the number of bass and mayflies in a lake in her hometown. Candice takes a sample of the pH level of the lake, and she finds that the pH level is 5.4. What might Candice predict as a result of her findings?A)The lake's pH level of 5.4 is safe for both bass and mayflies, but not for frogs.B)The lake's pH level of 5.4 will cause a decrease in the amount of bass and mayflies.C)The lake's pH level of 5.4 will affect the number of bass, but probably not the mayflies.D)The lake's pH level of 5.4 will not affect the survival of any of the animals listed in the chart.E)None of the aboveExplanation:This bar chart represents at the pH levels at which certain animals cannot live. The lower pH levels begin to negatively affect some animals. Bass and mayflies cannot live in a condition with a pH level below 5.5. Therefore, a pH level of 5.4 is extremely dangerous for both bass and mayflies. Candice can draw the conclusion, based on the chart, that?The lake's pH level of 5.4 will cause a decrease in the amount of bass and mayflies.?in her hometown.32)?Litmus paper is made from water-soluble dyes which are extracted from lichens. This paper is used as an acid-base indicator. Which of these common household substances would turn blue litmus paper red?A)bleachB)lyeC)soapD)vinegarE)None of the aboveExplanation:Blue litmus paper turn red in the presence of an acid, and?vinegar?is the only choice that is an acid. The rest of the choices are bases and blue litmus would stay blue when dipped in them.33)?Matthew was working with different concentrations of hydrochloric acid in the lab. Which of these would BEST describe the results Matthew would see if he was using a conductivity apparatus in each of the different acid concentrations?A)The bulb would burn the same in all concentrations.B)The light bulb would burn brightest in the weakest acid.C)The light bulb would burn brightest in the strongest acid.D)The light bulb would not burn as acids do not conduct electricity.E)None of the aboveExplanation:The light bulb would burn brightest in the strongest acid.?The stronger the acid, the more ions produced in solution, and the better conductor it is.34)According to this graph, a lake that has a pH level of 4A)has no fish.B)has many frogs.C)has few rainbow trout.D)is healthy and thriving.E)None of the aboveExplanation:This chart shows that a healthy lake has a pH of about 7. As this acidity increases, the pH will decrease. A lake with a ph level of only 4?has no fish.35)Sulfur emissions from industry combine with water in the atmosphere and form acid rain. A new factory is built very close to the lake that Josh visits often. By examining the table that shows what pH range different species can survive, Josh decides that the aquatic life will be affected by the changes in pH that the lake. Josh correctly decides that organisms that will be the most affected areA)perch and frogs.B)mayfly and bass.C)snails and clams.D)frogs and salamanders.E)None of the aboveExplanation:The answer is?snails and clams. Organisms can live in narrow range of pH. The pH level of the lake will drop with the acid rain and only those organisms that can survive acidic pH environment will survive.36)Consider the four salts represented on the solubility curves displayed as line graphs. In all four cases the salts are which part of an aqueous solution?A)precipitateB)soluteC)solvationD)solventE)None of the aboveExplanation:Each salt is a different?solute?dissolved in water, which would be the solvent. ................
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