PLEASE TURN IN YOUR SUMMATIVE LAB!

Transcription

1 PLEASE TURN IN YOUR SUMMATIVE LAB!

2 SUMMATIVE QUIZ 3 REVIEW Density Graphing

3 CALCULATING DENSITY Calculate the density for each of the trials. Show all work properly and report answers to correct significant figures. Enter your answers into the data table and write the correct units into the heading in the data table. (4 marks) 2.70 g/cm g/cm g/cm g/cm 3

4 GIVEN THE FOLLOWING DENSITIES, IDENTIFY THE UNKNOWN METAL. (1 MARK)

5 DEFINE PRECISION AND ACCURACY; USE YOUR CALCULATED DENSITIES TO SUPPORT YOUR ANSWER. (4 MARKS) Precision how close measurements are to each other Accuracy how close measurements are to the actual value Are the values precise? 2.70 g/cm 3, 2.51 g/cm 3, 2.66 g/cm 3, 2.75 g/cm 3 Are the values accurate? Average density value: 2.66 g/cm 3

6 GRAPHING (8 MARKS) Axes Labels (2) Title (1) Units (2) Scale (1) Plotting (1) LOBF (1)

7 QUIZ 3 RETAKE: Remember that you are able to retake one quiz a unit. There were three quizzes this unit. You are only allowed to retake a quiz up until the next quiz. This means that you can no longer retake quiz 1 or quiz 2. If you choose to retake quiz three, please come talk to me to schedule a retake.

8 POGIL REVIEW Significant Digits and Measurement

9 MODEL 1 RULER A 1. What distances can you be certain of on the ruler in Model 1? 0 cm, 10 cm 2. Were all of the students able to agree on a single value for any digit? The students did not agree on any values or digits. 3. How did each student divide up the ruler by eye in order to get the measurement that he or she recorded? Susan and Maya may have divided the ruler into 10 parts. Jonah divided it into fourths. Tony and Dionne divided it into thirds.

10 MODEL 2 RULER B 4. What distances can you be certain of on this ruler? 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 cm 5. Where the students able to agree on a single value? 3 6. What feature of the ruler in Model 2 made it possible for the students to agree on a value in that digit? The ruler has equal spaced markings from 0 10 cm 7. Which ruler resulted in greater variation? Model 1 measurements are more uncertain

11 MODEL 3 RULER C 8. The students obtained an even better ruler, shown above in Model 3. a. were the students able to agree on a single value for any of the digits in their measurements? All agreed on 3.2 b. What feature of the ruler in Model 3 made if possible for the students to agree on the values in those digits? Marks for ones place and tenths place

12 MODEL 4 VALID MEASUREMENTS 9. The measurements taken in Models 1-3 have been combined in Model 4. The measurements that follow the rules of measurements agreed upon by scientists are in the Valid Measurements column. Those that do not follow the rules are in the Invalid Measurements column. For each valid measurement shown in Model 4, draw a square around the certain digits (if any) and circle the digits that were estimated (if any). 10. Based on the examples in Model 4, circle the best phrase to complete each sentence below. a. In a valid measurement, you record (zero, one, two) estimated digit(s). b. In a valid measurement, the estimated digit is the (first digit, second to last digit, last digit) in the measurement. c. In a valid measurement, the estimated digit corresponds to (the largest marks, the smallest marks, one tenth of the smallest marks) on the instrument.

13 MODEL 4 VALID MEASUREMENTS 11. Using Ruler B from Model 4, Tony recorded a measurement of 3 cm. Explain why this was an invalid measurement. Estimated a tenth s place 12. Using Ruler B from Model 4, Dionne recorded a measurement of 3.20 cm, which was invalid. But when Maya made the same measurement using Ruler C, it was considered valid. Explain why the zero was acceptable when using Ruler C, but not when using Ruler B. Dionne should have a 100 th place Maya was correct 13. A student recorded the length of a test tube as 5.0 cm. Which ruler in Model 4 was the student using? Ruler B 14. In Model 4, Ricky recorded his measurement 3.19 cm using Ruler C. His classmates thought he was wrong because his second digit was not 2. However, Ricky s recorded measurement is perfectly valid. Explain. Ruler C has a 100 th place uncertainty

14 RECORDING MEASUREMENTS 15. Record the length of the wooden splint to the proper number of significant digits. 7.0 cm 16. Record the length of the wooden splint to the proper number of significant digits cm

15 EXTENSION QUESTIONS 17. When using an electronic device, such as an electronic balance, the measurement displayed on the screen is assumed to have one estimated digit included. In face, you ll often see the estimated digit changing rapidly, because there is fluctuation in the estimate. Explain why it is important to record the zero in the measurement shown to the right. 18. Consider a 1000-mL graduated cylinder with marks every 100-mL. a. A student records the volume of liquid in the cylinder as 750 ml. Is this a correct measurement? Yes, the 100 th place is certain and 10 th place estimated. b. Are all of the digits in the described measurement of 750 ml significant? 7 & 5 are significant, 0 is not 19. A student properly records the length of a block as 120 cm. Draw the markings on the ruler that was used to measure the block.

16 PERIODIC TABLE STATIONS REVIEW Science Skills Station Narrative Station Assessment Station

17 SCIENCE SKILLS STATION: ACTIVITY #1

18 SCIENCE SKILLS STATION: ACTIVITY #1 Are the majority of elements metals, metalloids, or non-metals? Metals What do you notice about the metallic character of elements as you move across (left to right) the Periodic Table? Metallic character of elements decreases Why are Noble gases inert (unreactive)? Noble gases have a full valence shell. They do not want to gain or lose electrons and interact with other atoms. Why are Alkali and Alkaline Earth metals very reactive? They have one and two valence electrons. They readily want to lose these electrons in order to become positive ions.

19 SCIENCE SKILLS STATION: ACTIVITY #2 Alkali Metals Halogen Nonmetal Metalloid Transition Metal Lanthanide (Rare Earth Metal) Actinide (Rare Earth Metal) Alkaline Earth Metal Noble Gas Soft, shiny, highly reactive Highly reactive nonmetals Dull, brittle, poor conductor, low melting pt. Like metals and non-metals High density and melting pt. Shiny, silvery metals, rare Radioactive Reactive, shiny, low density Inert/unreactive gases 1. One of the most commonly used elements in nuclear energy is naturally radioactive. This element is fissile, which means it can be split into smaller atoms, releasing large amounts of energy. This energy is harvested to create electricity. Which element in the table above is most likely this element? Uranium 2. This element is very reactive and often forms a +1 ion because it only have one valence electron. It is an important nutrient to the human body. Which element in the table above is most likely this element? Potassium 3. What is on other element that belongs to the same group as Carbon? Nitrogen, Oxygen, Phosphorus, Sulfur, Selenium, Hydrogen

20 NARRATIVE STATION: ACTIVITY #1 1. What is the Periodic Table of Elements? A way of organizing and displaying all the different elements. 2. The Periodic Table displays each element in a box. In most periodic tables, each box gives four pieces of information about an element. Label the pieces of information in the sample box. (Hydrogen) Atomic Number Element Symbol 3. What is the difference between a period and group? A period is a row, a group is a column. 4. How are elements arranged in the Periodic Table? By atomic number. Element Name Atomic Mass

21 NARRATIVE STATION: ACTIVITY # The suffix oid means resembling or like. Based on this meaning, why does it make sense that elements known as metalloids are called so? Metalloids are like metals because they resemble them. 3. Is there a trend in the metallic character of elements as you move across the periodic table? Metallic character decreases as you move across the Periodic Table.

22 ASSESSMENT STATION 1. How are elements arranged in the Periodic Table of Elements? By atomic number. 2. Elements are arranged in rows and columns in the periodic table. The rows are called. The columns are called. Rows = periods, Columns = groups 3. Compare and contrast the properties of a metal and nonmetal. Then classify the elements below as metallic or nonmetallic. Metals are hard, shiny, malleable, and good conductors (Sodium, Iron, Calcium) Nonmetals are brittle, dull, and poor conductors (Oxygen, Hydrogen, Argon) 4. Where do you find halogens and Nobel gases on the Periodic Table? Halogens are in group 17, Nobel gases are in group 18

23 ASSESSMENT STATION 5. Where do you find metalloids on the Periodic Table? Metalloids border the staircase on a periodic table, except for Aluminum. 6. Before today s modern periodic table, scientists attempted to organize elements by physical properties or weight (atomic mass). What are the pros and cons to organizing elements this way? Why is the organization of today s periodic table better? Atomic mass varies for elements. Physical properties tend to be similar for elements in the same group. Atomic number is a defining feature for atoms of the same element. 7. Are Alkali and Alkaline Earth Metals more likely to become positive or negative ions? What about nonmetals? Metals to the far left tend to become positive ions. Nonmetals tend to form negative ions. 8. All elements belonging to the actinides series are naturally radioactive. Why does this make sense? These elements are very large. Large atoms tend to be unstable because they have large nuclei. The nuclei break down and emit radiation to become stable.

24 MISSING ASSIGNMENTS! If you have missing assignments for this unit, the last day to turn them in is exam day. After exam day, you will no longer be able to turn in missing assignments and grades will be entered in as a zero. If you have missing assignments, please come talk to me.