REVIEW Lab Safety Lab Equipment Scientific Method Experimental

REVIEW Lab Safety Lab Equipment Scientific Method Experimental Design Graphing

True or False? 1. Eating and drinking is not permitted in the laboratory. 2. It is not necessary to wash your hands after every laboratory experiment.

True or False? 3. All sharp and pointed objects should be handles with extreme care. 4. It is unnecessary to report broken or chipped glassware or slides to the teacher.

True or False? 5. All glassware, equipment, and your work station area should be cleaned as soon as you have finished your investigation. 6. Goggles only need to be worn when performing dissections.

True or False? 7. When heating materials in a test tube, make sure the test tube is facing away from you and your partner. 8. Direct viewing of the sun is ok as long as you have sunglasses on.

True or False? 9. It is ok to dump a chemical down the sink. 10. If any glassware breaks, the student should clean it up right away.

11. If any glassware breaks, the student should clean it up right away. 12. Perform only those experiments for which you have been instructed.

13. Identify the lab safety violations (improper lab procedures) observed in the diagram.

14. Identify the lab safety violations observed in the diagram.

15. Identify the improper lab procedure observed in the diagram.

16. Identify the improper lab procedure observed in the diagram.

17. Identify the improper lab procedure observed in the diagram.

18. Identify the improper lab procedure observed in the diagram.

19. Identify the following pieces of lab equipment.

20. Identify the following pieces of lab equipment.

21. Identify the following pieces of lab equipment.

22. Identify the following pieces of lab equipment.

23. What is a hypothesis? 24. What step states whether the hypothesis is correct or incorrect? 25. Which step tests the hypothesis? 26. List the steps of the scientific method in order.

27. In your own words, identify the name/explain the purpose of each section. a. PROBLEM : b. c. HYPOTHESIS: d. EXPERIMENT: e. OBSERVATIONS: f. CONCLUSION: g.

28. DEFINE THE PARTS OF A CONTROLLED EXPERIMENT a. control group: b. experimental group: c. independent variable: d. dependent variable:

29. The problem of an experiment is in the form of a ____. 30. A ______ is an educated guess to the problem of the experiment. 31. The ______ states whether your hypothesis is correct or incorrect. 34. What would make the results of an experiment carried out by a research team valid?

35. Problem: Will bread last longer if it is kept in the refrigerator? For this experiment, identify the: a. IV: b. DV: c. Experimental Group: d. Control Group: e. Constants:

36. Mrs. Wood keeps a container of crickets in the science lab so she can feed the critters. Lately they are chirping more than usual. She remembers reading somewhere that the chirping of crickets depends on the air temperature at which they live. You want to do a controlled experiment to see if this is true. a. Write a PROBLEM for the investigation. b. Write a hypothesis for your question. c. What is the independent variable? d. What is the dependent variable? e. What is the experimental group? f. What is the control group? e. List at least two constants for this investigation.

37. The table below contains data from Mrs. Wood’s investigation. Use this data to answer the questions Temperature Chirps per Minute below. 12°C 0 18°C 23°C 29°C 34°C 38°C 24 33 42 4 0 Which graph has properly labeled axes? Circle your choice. 38. What would be a good title for a graph representing this data?

39.

40. To test the effect of hormones on plant growth, the growth of 6 potted plant seedlings of the same species were measured and then sprayed with a growth hormone. After 4 weeks of growth under ideal conditions, the plants were measured again. a. How would you set up the control group? b. Identify the independent and dependent variables. c. Give 2 factors that must be kept constant.

41. You studied the effect of the amount of fish food on the mass of goldfish. One tank of goldfish is fed the normal amount of food once a day. A second tank of goldfish was fed twice a day. A third tank of goldfish was fed three times a day. The fish's mass was measured three times a week. a. State the problem. b. Give a possible hypothesis. c. Identify the independent variable. d. Identify the control group. e. Identify the dependent variable. f. Identify 2 constants

42. An experiment was done in which the heart rate of water fleas were measured after being placed in water at different temperatures. a. IV b. DV c. How would you label each axis on a line graph for this experiment? d. What would be a proper title for this experiment?

43. e. State the relationship between the average water flea heart rate and water temperature. 280 260 240 220 200 f. What is the average flea heart rate at 15ºC? 180 160 140 120 g. What is the average flea heart rate at 30ºC? 100 80 60 40 20 5 35 10 15 20 25 30

44. Problem: Does an electric motor turn faster if you increase the voltage? a. IV b. DV c. 1 constant

45. Problem: Does heating a cup of water allow it to dissolve more sugar? a. IV b. DV c. 2 constants

46. Problem: Does fertilizer affect the growth of plants? a. IV b. DV c. 2 constants

47. a. Identify the independent and dependent variables. b. State the relationship between the number of frogs in the pond. c. How many frogs are present when there is 15 cm of spring rainfall?

48. You want to test which size soccer is easier to juggle with your feet. You test the size 3, size 4, and size 5 ball. You count the number of seconds the ball stays in the air for each trial. You allow yourself to use both feet, knees and head to juggle the ball. a. Identify the independent variable. b. Identify the dependent variable. c. What can be done to increase the validity of the experiment.

49. The results of one experiment carried out by a research team would be considered valid if 1. the experiment had no control setup 2. all the members of the research team came to the same conclusion 3. the experiment had more than one variable 4. the experiment was repeated and the same results were obtained each time 50. Why do scientists make graphs of data from experiments? 1. to observe general trends and patterns in the data 2. to make the observed data more accurate 3. to prevent errors in measuring data 4. to help change the original data tables

51. An investigation is carried out to determine the effect of exercise on the rate at which a person can squeeze a clothes pin. In this investigation, the independent variable is the 1. control 2. exercise 3. rate of squeezing 4. number of participants 52. An investigation is carried out to determine the effect of exercise on the rate at which a person can squeeze a clothes pin. In this investigation, the dependent variable is the 1. control 2. exercise 3. rate of squeezing 4. number of participants

53. Jason believed that oil poured faster when it was warmer. He created an experiment where he warmed the oil to different temperatures and timed how long the oil took to fill a beaker to 50 mm. a. Independent Variable b. Dependent Variable c. Constants d. Control

54. Adam thought that the heavier a person was, the faster they would be able to roller blade down a hill. He created an experiment to see if he was correct. He got a skateboard and timed how long it took to reach the bottom of the hill, he then put different weights on the skateboard and timed how long it took to reach the bottom of the hill with the different amounts of weight. a. Independent Variable b. Dependent Variable c. Constants d. Control

55. Emilio believed that the more someone exercised the faster their heart would beat. He created an experiment that had 25 of his friends running in place. He timed their heart rate when they started running and then every 15 seconds for 30 minutes. a. Independent Variable b. Dependent Variable c. Constants d. Control

56. Jenny’s mom was telling her a story about how her grandmother would always add aspirin to the water before watering her plants. Jenny decided she would find out if it really made a difference and thought it probably did. Jenny hypothesized that the more aspirin she used, the more the plants would grow. She conducted an experiment with 4 different amounts of aspirin (including one without aspirin) and she used 10 bean plants for each amount. a. Independent Variable b. Dependent Variable c. Constants d. Control

57. To investigate the effect of a substance on plant growth, 2 bean plants of the same species were grown under identical conditions with Substance Z added to the soil of one of the plants. At the end of 2 weeks, the plant grown with Substance Z was 12. 5 cm tall. The plant grown without Substance Z was 12. 2 cm tall. The researcher concluded that the presence of Substance Z causes the plants to grow taller. a. What is the independent variable? b. What is the dependent variable? c. Which setup is the control?

58. How bright is right? An automobile manufacturer wants to know how bright brake lights should be in order to minimize the time required for the driver of a following car to realize that the car in front is stopping and to hit the brakes. a. What is the independent variable? b. What is the dependent variable?

59. A student placed 5 geranium plants of equal size in 5 environmental chambers. Growing conditions were the same for each plant except for the amount of water each received. At the end of 20 days, plant growth was measured. a. What is the independent variable? b. What is the dependent variable?

60. The higher the temperature of water, the faster an egg will boil. a. Independent variable b. Dependent variable

Graphing 61. In an investigation, plants of the same species and the same initial height were exposed to a constant number of hours of light each day. The number of hours per day was different for each plant, but all other environmental factors were the same. At the conclusion of the investigation, the final height of each plant was measured. The following data were recorded: • Using the information given, construct a line graph on the grid provided, following the directions below. • a. Label each axis with the appropriate units. • B. Mark an appropriate scale on each axis. • c. Plot the data for final height on the grid. • d. Create a title for this graph. Write it in the space provided above the graph. Daily Light Exposure (hrs) Final Height (cm) 2 5 4 12 6 18 8 25 10 34 12 35 14 37

Daily Light Final Exposure Height (hrs) (cm) 2 5 4 12 6 18 8 25 10 34 12 35 14 37 e. What is the dependent variable? f. What type of relationship exists between the 2 variables in this experiment?