The safest way to dilute concentrated sulfuric acid is to add ___ A. a series of small volumes of water to the acid while stirring B. the acid to water slowly while stirring constantly C. the acid to a small volume of water and then add more water D. dilute sulfuric acid to a small volume of the concentrated acid 1A Bio 11-03

The safest way to dilute concentrated sulfuric acid is to add ___ A. a series of small volumes of water to the acid while stirring B. the acid to water slowly while stirring constantly C. the acid to a small volume of water and then add more water D. dilute sulfuric acid to a small volume of the concentrated acid

28 February Add acid to water

2. Scientific Processes Biology and Integrated Physics and Chemistry The student uses scientific methods during field and laboratory investigations. The student is expected to: A) Plan and implement investigative procedures including asking questions, formulating testable hypothesis, and selecting equipment and technology; B) Collect data and take measurements with precision; C) organize, analyze, evaluate, make inferences, and predict trends from data; and D) Communicate valid conclusions.

2A Bio A The table shows times required for water to evaporate from identical containers. Which of these is the best question to ask before developing a reasonable hypothesis to explain the data? A Why does a lower temperature slow the rate of evaporation? B What is the boiling point of the water after both samples are heated? C Why does water exist as a solid at -15 o C and as a liquid at 25 o C? D How does the rate of evaporation change when a different container is used? Time Required for Water Evaporation ContainerAB Volume of Water (mL) 25 Temperature ( o C) Time Required (h) 7224

2A Bio A The table shows times required for water to evaporate from identical containers. Which of these is the best question to ask before developing a reasonable hypothesis to explain the data? A Why does a lower temperature slow the rate of evaporation? B What is the boiling point of the water after both samples are heated? C Why does water exist as a solid at -15 o C and as a liquid at 25 o C? D How does the rate of evaporation change when a different container is used? Time Required for Water Evaporation ContainerAB Volume of Water (mL) 25 Temperature ( o C) Time Required (h) 7224

2 March Temp/evaporation: read the data fields

2A Bio B Which question is valid in testing this hypothesis? A Do most other scientists agree with the hypothesis? B Could abiotic processes account for the carbon dioxide? C What is the percent of argon compared to carbon dioxide in the Martian atmosphere? D Have the scientist’s other predictions about Mars been validated? A scientist has hypothesized that the existence of life on Mars is likely because Mar’s atmosphere is 95% carbon dioxide.

2A Bio B Which question is valid in testing this hypothesis? A Do most other scientists agree with the hypothesis? B Could abiotic processes account for the carbon dioxide? C What is the percent of argon compared to carbon dioxide in the Martian atmosphere? D Have the scientist’s other predictions about Mars been validated? A scientist has hypothesized that the existence of life on Mars is likely because Mar’s atmosphere is 95% carbon dioxide.

3 March How else could Mars get CO 2 ?

2A Bio D 11/06 Which of the following is the most likely hypothesis for the experiment described above? A Vegetation that grows near roadways requires more water than vegetation in other areas. B De-icing solution causes roadways to have more space for vegetation. C Vegetation near roadways changes the effectiveness of de-icing solution. D De-icing solution affects some types of vegetation that grows near roadways. A De-Icing Experiment Some species of plants that commonly grow near roadways are used in an experiment. The plant species are divided into control groups and experimental groups. All groups are grown under identical conditions except that the experimental groups are given daily applications of a de-icing solution that is used on roadways in winter. At the end of one month, the growth of the control group and experimental groups is compared.

2A Bio D 11/06 Which of the following is the most likely hypothesis for the experiment described above? A Vegetation that grows near roadways requires more water than vegetation in other areas. B De-icing solution causes roadways to have more space for vegetation. C Vegetation near roadways changes the effectiveness of de-icing solution. D De-icing solution affects some types of vegetation that grows near roadways. (4 March) A De-Icing Experiment Some species of plants that commonly grow near roadways are used in an experiment. The plant species are divided into control groups and experimental groups. All groups are grown under identical conditions except that the experimental groups are given daily applications of a de-icing solution that is used on roadways in winter. At the end of one month, the growth of the control group and experimental groups is compared.

2A Bio D 11/06 Beaker 1 Beaker 2 Beaker 3 (10 cm from light)(50 cm from light) (90 cm from light) The picture shows an experiment designed to investigate biochemical activity in a water plant in a dark room. Over time, bubbles can be easily observed and counted as they escape the funnel. The number of bubbles is an indicator of the rate of photosynthesis. Which of these data tables best reflects that expected results of this experiment? BeakersNumber of Bubbles/Minute A BeakersNumber of Bubbles/Minute BeakersNumber of Bubbles/Minute BeakersNumber of Bubbles/Minute B C D

2A Bio D 11/06 Beaker 1 Beaker 2 Beaker 3 (10 cm from light)(50 cm from light) (90 cm from light) The picture shows an experiment designed to investigate biochemical activity in a water plant in a dark room. Over time, bubbles can be easily observed and counted as they escape the funnel. The number of bubbles is an indicator of the rate of photosynthesis. Which of these data tables best reflects that expected results of this experiment? BeakersNumber of Bubbles/Minute A BeakersNumber of Bubbles/Minute BeakersNumber of Bubbles/Minute BeakersNumber of Bubbles/Minute B C D

21 March Plant closest to light has fastest photosynthesis.

2A Bio B In experiments, a benefit of larger sample sizes would be more --- A. variables B. representative data C. time per group D. control groups

2A Bio B In experiments, a benefit of larger sample sizes would be more --- A. variables B. representative data C. time per group D. control groups

22 March Larger sample = more representative data

2A BIO C An engineer has created a new engine for race cars. It is necessary to know which fuel mixture will allow the engine to run at its peak performance. Which experimental design is best for this investigation? A. Use one fuel mixture on the engine and measure its performance B. Use one fuel mixture on many types of engines and measure their performance C. Use various fuel mixtures on the engine and measure its performance D. Use various fuels on many types of engines and measure their performance

2A BIO C An engineer has created a new engine for race cars. It is necessary to know which fuel mixture will allow the engine to run at its peak performance. Which experimental design is best for this investigation? 23 March A. Use one fuel mixture on the engine and measure its performance B. Use one fuel mixture on many types of engines and measure their performance C. Use various fuel mixtures on the engine and measure its performance (Test various fuel mixtures on engine) D. Use various fuels on many types of engines and measure their performance

2A Bio B The following boxes represent a field. Which pattern for collecting 10 samples would provide the best data for identifying the types of plants in a field? X X X X X A X X X X X X X B X X X X X X X C X X X X X X X X X X X X D X X X X X

2A Bio B The following boxes represent a field. Which pattern for collecting 10 samples would provide the best data for identifying the types of plants in a field? X X X X X A X X X X X X X B X X X X X X X C X X X X X X X X X X X X D X X X X X

24 March Random sampling = best data

2A Bio H C Two science students discovered that the mass of a sample of acetone in an open beaker decreased within a few minutes. One student hypothesized that the acetone reacted with oxygen to form a gaseous compound that escaped. The other believed that the acetone evaporated into the air. What should the students do to test these hypotheses? A. Combine the hypotheses so they give valid predictions of the acetone’s behavior B. Conduct a study of original papers describing the experiments leading to acetone’s discovery C. Perform an experiment that attempts to identify the gas above the open beaker D. Ask a classmate’s opinion about the chemical and physical properties of acetone

2A Bio H C Two science students discovered that the mass of a sample of acetone in an open beaker decreased within a few minutes. One student hypothesized that the acetone reacted with oxygen to form a gaseous compound that escaped. The other believed that the acetone evaporated into the air. What should the students do to test these hypotheses? 28 March A. Combine the hypotheses so they give valid predictions of the acetone’s behavior B. Conduct a study of original papers describing the experiments leading to acetone’s discovery C. Perform an experiment that attempts to identify the gas above the open beaker D. Ask a classmate’s opinion about the chemical and physical properties of acetone

2A Bio A 11/05 Which study would most likely be used to investigate this hypothesis? A Tracking dust clouds with satellite photos B Determining the effects of iron on limestone C Calculating erosion rates in African limestone mines D Analyzing the content of comet dust clouds The following hypothesis refers to iron in the topsoil on an island formed from limestone. Hypothesis: Much of the iron found in the topsoil of the island was carried from Africa by huge dust clouds.

2A Bio A 11/05 Which study would most likely be used to investigate this hypothesis? 29 March A Tracking dust clouds with satellite photos B Determining the effects of iron on limestone C Calculating erosion rates in African limestone mines D Analyzing the content of comet dust clouds The following hypothesis refers to iron in the topsoil on an island formed from limestone. Hypothesis: Much of the iron found in the topsoil of the island was carried from Africa by huge dust clouds.

2A Bio D 11/05 According to these data, which question was most likely by this activity? A How warm do materials get when placed in an electric circuit? B Will an electric current change a metal into a nonmetal? C Which material requires the greatest voltage in an electric circuit? D Can an electric current be used to distinguish metals from other materials? MaterialConducts No Electricity Yes CopperX GlassX ChalkX SilverX WoodX SulfurX TinX ZincX Experimental Results

2A Bio D 11/05 According to these data, which question was most likely by this activity? (30 March) A How warm do materials get when placed in an electric circuit? B Will an electric current change a metal into a nonmetal? C Which material requires the greatest voltage in an electric circuit? D Can an electric current be used to distinguish metals from other materials? MaterialConducts No Electricity Yes CopperX GlassX ChalkX SilverX WoodX SulfurX TinX ZincX Experimental Results

2A Bio D 11/04 Which set of equipment would be best to use to test the effect of temperature on solution acidity? A A balance and a thermometer B A pH meter and a barometer C A balance and litmus paper D A thermometer and a pH meter

2A Bio D 11/04 Which set of equipment would be best to use to test the effect of temperature on solution acidity? A A balance and a thermometer B A pH meter and a barometer C A balance and litmus paper D A thermometer and a pH meter

1 April Temperature = thermometer; acidity = pH meter.

2A Bio C 11/04 A ruler placed between one student’s fingers and thumb is released without warning. A second student catches the ruler. The distance the ruler falls is recorded. This experiment is most likely designed to determine the --- A effects of stress on the first student’s heart rate B acceleration of the ruler during its fall C second student’s reaction time to a stimulus D force applied on a falling mass

2A Bio C 11/04 A ruler placed between one student’s fingers and thumb is released without warning. A second student catches the ruler. The distance the ruler falls is recorded. This experiment is most likely designed to determine the --- A effects of stress on the first student’s heart rate B acceleration of the ruler during its fall C second student’s reaction time to a stimulus D force applied on a falling mass

4 April Experiment tests 2 nd student’s reaction time.

2A Bio D 10/03 Objects of the same mass but of different sizes and shape were dropped from a given height. Their rates of free fall were measured and recorded. Which of the following is most likely the question this experiment was designed to answer? A How does height affect the force of gravity? B How does gravity affect objects of different densities? C How do mass and weight affect falling objects? D How do size and shape affect an object’s rate of free fall?

2A Bio D 10/03 Objects of the same mass but of different sizes and shape were dropped from a given height. Their rates of free fall were measured and recorded. Which of the following is most likely the question this experiment was designed to answer? A How does height affect the force of gravity? B How does gravity affect objects of different densities? C How do mass and weight affect falling objects? D How do size and shape affect an object’s rate of free fall? (5 April)

2A Bio B 10/04 Which lab setup would be appropriate to use in heating 100 mL of water to the boiling point? A A 10 mL test tube held above a Bunsen burner B A 200 mL beaker placed on a hot plate C A thermal coil inside a 100 mL cylinder D A sealed 300 mL flask in a warm-water bath

2A Bio B 10/04 Which lab setup would be appropriate to use in heating 100 mL of water to the boiling point? A A 10 mL test tube held above a Bunsen burner B A 200 mL beaker placed on a hot plate (6 April) C A thermal coil inside a 100 mL cylinder D A sealed 300 mL flask in a warm-water bath

2A Bio C 11/06 A medical researcher hypothesizes that a newly developed medication can reduce high blood pressure. Which of these would most likely be the dependent variable in a study involving this medication? A The number of participants in the study B The ages of people treated for high blood pressure with other medication C The blood pressure of the participants in the study D The number of people treated for high blood pressure with other medications

2A Bio C 11/06 A medical researcher hypothesizes that a newly developed medication can reduce high blood pressure. Which of these would most likely be the dependent variable in a study involving this medication? A The number of participants in the study B The ages of people treated for high blood pressure with other medication C The blood pressure of the participants in the study D The number of people treated for high blood pressure with other medications

7 April Med study: blood pressure = dependent variable

2A Bio C 11/06 A medical researcher hypothesizes that a newly developed medication can reduce high blood pressure. Which of these would most likely be the dependent variable in a study involving this medication? A The number of participants in the study B The ages of people treated for high blood pressure with other medication C The blood pressure of the participants in the study D The number of people treated for high blood pressure with other medications

2A Bio D 11/06 Similar sprigs of elodea were placed in four test tubes. Each test tube contained water with a different concentration of salt ranging from 0 to 3 percent. The length of each sprig was measured after 10 days. Which of these questions can best be answered with this experimental setup? A Can the amount of salt in the water help elodea avoid disease? B What happens to salt as elodea sues water? C Will elodea increase the amount of salt in the water? D Does the amount of salt in the water affect elodea growth?

2A Bio D 11/06 Similar sprigs of elodea were placed in four test tubes. Each test tube contained water with a different concentration of salt ranging from 0 to 3 percent. The length of each sprig was measured after 10 days. Which of these questions can best be answered with this experimental setup? A Can the amount of salt in the water help elodea avoid disease? B What happens to salt as elodea sues water? C Will elodea increase the amount of salt in the water? D Does the amount of salt in the water affect elodea growth? (11 April)

11 April How does salt affect elodea growth?

2A Bio A 11/05 A valid study would include a control group containing --- A bean seed, tomato seed, sunflower seed, an water B water and 2% root hormone C water only D bean seed, tomato seed, sunflower seed, water, and 1% root hormone

2A Bio A 11/05 A valid study would include a control group containing --- A bean seed, tomato seed, sunflower seed, and water B water and 2% root hormone C water only D bean seed, tomato seed, sunflower seed, water, and 1% root hormone

12 April Control contains all but one variable

2A Bio A Which of the following was probably the hypothesis for this experiment? A The growth of bread mold increases as temperature increases. B The type of nutrient causes bread mold to grow faster at higher temperatures. C The size of the plates determines the temperature of bread mold. D The temperature of bread mold is determined by the mold’s growth. Students placed equal amounts of bread mold on 12 identical agar plates containing the same amounts and types of nutrients. Four plates were kept at 0 o C, four were kept at 45 o C, and four were kept at 22 o C (room temperature). The plates were examined after five days.

2A Bio A Which of the following was probably the hypothesis for this experiment? A The growth of bread mold increases as temperature increases. B The type of nutrient causes bread mold to grow faster at higher temperatures. C The size of the plates determines the temperature of bread mold. D The temperature of bread mold is determined by the mold’s growth. Students placed equal amounts of bread mold on 12 identical agar plates containing the same amounts and types of nutrients. Four plates were kept at 0 o C, four were kept at 45 o C, and four were kept at 22 o C (room temperature). The plates were examined after five days.

13 April Warmer temp = faster mold growth

2A Bio C Moon Chemistry Samples collected by Apollo astronauts have provided new data about the moon. Some of these samples consisted of lunar soil, a fine-grained, sand-like material produced as a result of the destruction of moon rocks. Traces of beryllium-10 were found in the samples. Beryllium-10 is carried by the solar wind, which transports elements from the sun’s surface and deposits them on the moon. The solar wind may also result in the formation of new substances. Tiny teardrops of iron and specks of molybdenum were found inside the particles of lunar soil. This is interesting because these elements have not been found in an uncombined state on Earth. The metal oxides they originally were part of were possibly changed when bombarded by the positively charged particles of the solar wind. Another interesting find was tiny (1 to 3 micrometers in length) crystals of silver sulfide. Because similar particles are found on Earth, it has been hypothesized that these crystals were created at a time when the moon had a molten core. Which procedure is best to use when determining the density of a rock? A. Place the rock in a water-filled beaker and find the height at which the rock floats above water. B. Use a ruler to measure the rock’s dimensions and then find its mass using an analytical balance. C. Measure the mass of the rock on a balance and then find the volume of water it displaces in a graduated cylinder. D. Place the rock in three liquids with different densities and observe which liquid the rock floats in.

2A Bio C Moon Chemistry Samples collected by Apollo astronauts have provided new data about the moon. Some of these samples consisted of lunar soil, a fine-grained, sand-like material produced as a result of the destruction of moon rocks. Traces of beryllium-10 were found in the samples. Beryllium-10 is carried by the solar wind, which transports elements from the sun’s surface and deposits them on the moon. The solar wind may also result in the formation of new substances. Tiny teardrops of iron and specks of molybdenum were found inside the particles of lunar soil. This is interesting because these elements have not been found in an uncombined state on Earth. The metal oxides they originally were part of were possibly changed when bombarded by the positively charged particles of the solar wind. Another interesting find was tiny (1 to 3 micrometers in length) crystals of silver sulfide. Because similar particles are found on Earth, it has been hypothesized that these crystals were created at a time when the moon had a molten core. Which procedure is best to use when determining the density of a rock? A. Place the rock in a water-filled beaker and find the height at which the rock floats above water. B. Use a ruler to measure the rock’s dimensions and then find its mass using an analytical balance. C. Measure the mass of the rock on a balance and then find the volume of water it displaces in a graduated cylinder. D. Place the rock in three liquids with different densities and observe which liquid the rock floats in.

14 April For rock density: mass on balance, volume from water displacement.

2A Bio A 10/03 Which of these is a hypothesis that can be tested through experimentation? A Bacterial growth increases exponentially as temperature increases. B A fish’s ability to taste food is affected by the clarity of aquarium water. C Tadpoles’ fear of carnivorous insect larvae increases as the tadpoles age. D The number of times a dog wags its tail indicates how content the dog is.

2A Bio A 10/03 Which of these is a hypothesis that can be tested through experimentation? A Bacterial growth increases exponentially as temperature increases. B A fish’s ability to taste food is affected by the clarity of aquarium water. C Tadpoles’ fear of carnivorous insect larvae increases as the tadpoles age. D The number of times a dog wags its tail indicates how content the dog is.

15 April Experiment can test bacterial growth/temperature.

2A Bio B 11/06 A student is working with four beakers that each contain a clear liquid. Which set of procedures would be best to use to determine whether one of the beakers contains only distilled water?

2A Bio B 11/06 A student is working with four beakers that each contain a clear liquid. Which set of procedures would be best to use to determine whether one of the beakers contains only distilled water? 18 April: H 2 O: odor, pH, density, boiling pt

2A Bio B 11/05 Only 10% of the electrical energy operating a lightbulb is changed into visible light. Which instrument helps identify the energy change occurring to most of the remaining 90%? A Triple-beam balance B Thermometer C Magnifying glass D Prism

2A Bio B 11/05 Only 10% of the electrical energy operating a lightbulb is changed into visible light. Which instrument helps identify the energy change occurring to most of the remaining 90%? A Triple-beam balance B Thermometer C Magnifying glass D Prism

19 April Electricity to light energy… lose heat