Intro to Mastering Chemistry

5. Part A Correctly classify the given food items as either a fruit or a vegetable. If you need help, look at the hint available by clicking Hints. Drag the foods into the appropiate bins. Fruits should be placed in the left bin. Vegetables should be placed in the right bin.

Fruit: tomato, apple, banana, and avocado Vegetable: potato and carrot

6. Part A Each of these geometric shapes has a different number of sides. Arrange the shapes in order from the shape with the greatest number of sides to the shape with the fewest number of sides. Rank these shapes from greatest to fewest number of sides. To rank items as equivalent, overlap them.

Greatest Number of sides: Octagon Next: Hexagon Next: Pentagon Next: Overlap Square and Rectangle (have the same number of sides) Fewest number of sides: Triangle

3. Part A Suppose you are asked to find the area of a rectangle that is 2.1-cm wide by 5.6-cm long. Your calculator answer would be 11.76 cm2 . Now suppose you are asked to enter the answer to two significant figures. (Note that if you do not round your answer to two significant figures, your answer will fall outside of the grading tolerance and be graded as incorrect.) Enter your answer to two significant figures and include the appropriate units. Part B What value should you use as the area of the base when calculating the answer to Part C? A. 11.8 cm^2 B. 11.76 cm^2 C. 12 cm^2 Part C Using the correct answer from Part B, calculate the volume of a rectangular prism with a length of 5.6 cm, a width of 2.1 cm, and a height of 6.6 cm. The figure shows a rectangular prism with length L equal to 5.6 centimeters, width W equal to 2.1 centimeters, and height H equal to 6.6 centimeters. Enter your answer to two significant figures and include the appropriate units. Part D Would an answer that generated the response below be considered correct and give you full credit? A feedback massage for an incorrect number of significant figures is shown. A. No. B. It is impossible to tell. C. Yes.

Part A: 12 cm^2 Part B: 11.76 cm^2 Part C: 78 cm^3 Part D: Yes

4. Part A Enter the molecular formula for butane, C4H10. Express your answer as a chemical formula. C4H10 Part B Enter the symbol of a sodium ion, Na+, followed by the formula of a sulfate ion, SO42−. Separate the ions with a comma only—spaces are not allowed. Express your answers as ions separated by a comma. Part C Enter the expression 14 (top) 7 (bottom) N+α, where α is the lowercase Greek letter alpha. Express your answer as a chemical expression. Part D Enter the chemical equation 2H^+(aq)+S^2−(aq)→H2S(g). Express your answer as a chemical equation.

Part A: C4H10 Part B: Na^+, SO4^2- Part C: 14 (top) 7 (bottom) N+α Part D: 2H^+(aq)+S^2−(aq)→H2S(g)

1. Part A How many squares are in this 2×2 grid (Figure 1) ? Note that the figure link lets you know that a figure goes along with this part. This figure is available to the left. Enter your answer as a number in the box below and then submit your answer by clicking Submit. Part B What is the magic number? (Figure 2) Note that there is a figure also associated with this part. However, the figure for Part A may still be visible on the left. To view the figure associated with Part B, click on the figure link. A new figure should appear on the left. You could try to guess the magic number but you would probably use up all your tries before getting the answer. Notice the new Hints button underneath the answer box for this question. Clicking this button will open up a list of hints that will guide you to the correct number. Part C Multiple-choice questions have a special grading rule determined by your instructor. Assume that your instructor has decided to grade these questions in the following way: If you submit an incorrect answer to a multiple-choice question with n options, you will lose 1/(n−1) of the credit for that question. Just like the similar multiple-choice penalty on most standardized tests, this rule is necessary to prevent random guessing.If a multiple-choice question has five answer choices and you submit one wrong answer before getting the question correct, how much credit will you lose for that part of the question? A. 100% B. 50% C. 33% D. 25% E. 20%

Part A: Number of squares = 5 Part B: Magic number = 60 Part C: Credit lost = 25%

7. Part A You are starting a new item and after reading the first part you realize you have no idea how to go about answering it. What should you do? A. Use the available hints. B. Request the solution immediately. C. Guess randomly and hope for some useful feedback. Part B You have been working on an item for a while and after a few missteps you've come up with an answer. However, there is one particular thing that you're not 100% sure of. What should you do? Select all that apply. A. Check for any hints that address the part of the calculation you're unsure about. B. Return to the question after you've spoken with an instructor or classmate. C. Submit your answer and then adjust it according to any feedback you receive. None of the above. Part C You've just solved a problem and the answer is the mass of an electron, me=9.11×10−31kilograms. How would you enter this number into the answer box? Enter your answer in kilograms using three significant figures. Note that the units are provided for you to the right of the answer box. Part D A friend in your class tells you that she never uses hints when doing her Mastering homework. She says that she finds the hints helpful, but when the hint asks another question it increases the chance that her score on the problem will go down. She feels like it isn't worth the risk.You reassure her that there is nothing to fear about opening a hint that asks a question. Which of the following are good reasons for your friend not to worry? Select all that apply. A. The only way to lose additional partial credit on a hint is by using the "give up" button or entering incorrect answers. Leaving the question blank will not cost you any credit. B. As an incentive for thinking hard about the problem, your instructor may choose to apply a small hint penalty, but this penalty is the same whether the hint simply gives information or asks another question. C. Getting the correct answer to the question in a hint actually gives you some partial credit, even if you still can't answer the original question. D. None of the above.

Part A: Use the available hints. Part B: (check mark boxes A, B, and C) A. Check for any hints that address the part of the calculation you're unsure about. B. Return to the question after you've spoken with an instructor or classmate. C. Submit your answer and then adjust it according to any feedback you receive. Part C: me = 9.11×10^−31 kilograms Part D: (check mark boxes A, B, and C) A. The only way to lose additional partial credit on a hint is by using the "give up" button or entering incorrect answers. Leaving the question blank will not cost you any credit. B. As an incentive for thinking hard about the problem, your instructor may choose to apply a small hint penalty, but this penalty is the same whether the hint simply gives information or asks another question. C. Getting the correct answer to the question in a hint actually gives you some partial credit, even if you still can't answer the original question.

2. Part A For most answers, you will simply enter your numeric answer directly into the space provided to the right of the equal sign. Answer the following question by typing the numeric answer into the answer box. If you have a gross of items, you have 144 items. If you buy a gross of eggs, how many dozen eggs do you have? Express your answer in dozens. Do not enter the units; they are provided to the right of the answer box. Part B When entering large numbers in the answer box, do not use commas. For example, enter 1276400 for the number 1,276,400. Do not enter 1,276,400. If you accidentally enter commas, you will get a message that your answer is incorrect. Answer the following question by typing the numeric answer into the answer box. What is the sum of 9260 and 3240? Express your answer numerically to at least three significant figures. Part C Practice entering numbers that include a power of 10 by entering the diameter of a hydrogen atom in its ground state, dH=1.06×10−10m, into the answer box. Express the diameter of a ground-state hydrogen atom in meters using a power of 10. Do not enter the units; they are provided to the right of the answer box. Part D If you are asked to provide a set of two or more numeric answers, separate them with commas. For example, to provide the year that Sputnik (the first satellite to be sent into orbit around the Earth) was launched and the year humans first walked on the Moon, you would enter 1957,1969 in the answer box. A rectangle has a length of 5.50 m and a width of 12.0 m. What are the perimeter and area of this rectangle? Enter the perimeter and area numerically separated by a comma. The perimeter should be given in meters and the area in square meters. Do not enter the units; they are provided to the right of the answer box.

Part A: number of eggs = 12 dozen Part B: sum = 12500 Part C: dH = 1.06×10^−10m Part D: Perimeter = 35.0m Area = 66.0m^2