Chemistry

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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. *I'm going to go ahead and add the hints here for you to help you in the future* Hint* How many items are in a dozen? Hint 1: *If you have a dozen items, how many items do you have?* 12 items

How to solve. A dozen eggs is 12 eggs. If you have 144 eggs and need to calculate the number of dozens of eggs... take 144 eggs/12 eggs and that gives you 12 dozen. The answer is 12 dozen

You can enter compound units that are combinations of other units that are multiplied together. To enter the ⋅⋅ explicitly, type (shift + 8) on the keyboard, or use the template in the Templates menu. Torque can be calculated by multiplying the force (N) applied at 90∘ to the lever arm at a distance (mm) from the pivot point (point of rotation), the compound SI unit for the torque is N⋅m If the force (at 90∘to the lever arm) applied is 15 N and it is applied at 2.0 m from the pivot point (point of rotation), what is the torque on the lever? Express the torque with the appropriate units. Hint The equation for computing torque If a lever has a constant force applied at 90∘90∘ to the lever arm at a fixed distance from the pivot point (point of rotation), the torque on the lever is given by torque = force (at 90∘ to lever arm) × distance to pivot point

How to solve: 15 is N and 2.0 is m 15 * 2 = 30 Answer is 30 N*m (be sure that the N is capital and the m is little)

How can you use Mastering to develop a growth mindset and embrace your mistakes?

Question what went wrong and use hints or provide problem feedback to develop a new strategy

Enter the symbol of a sodium ion, Na+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.

Na+,SO42− (+ is upper. 4 is subscript. 2- is upper)

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.

Octagon hexagon Pentagon Rectangle and Square on top of each other Triangle

What value should you use as the area of the base when calculating the answer to Part C? 12 cm^2 11.8 cm^2 11.76 cm^2

11.76 cm^2

You may want to enter 367,000,000 in scientific notation as 3.67×1083.67×108. There are two ways to do this. To use a template, click the button found under the menu. To use the keyboard, Instead of the ×× symbol, use a multiplication dot (⋅⋅) by typing the keyboard multiplication symbol * (usually Shift + 8). To input the exponent for numbers written in scientific notation, do either of the following:Click the button found under the menu.Type ^ (Shift + 6) from your keyboard. For example, 3.67⋅1083.67⋅108 can be entered in the answer box by typing 3.67*10^8. Practice entering numbers that include a power of 10 by entering the diameter of a hydrogen atom in its ground state, dH=1.06×10−10mdH=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.

1.06*10^-10

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. The grid is a square cut into 4's. It's easy to think the answer is 4 but people forget to count the square around the outside.

Answer = 5

How do people with a growth mindset view and respond to challenges?

They see challenges as opportunities to learn and push their abilities. Submit

Answer the following question by entering the numeric value with appropriate units. If the length of one side of a square is 12.0 mm, what is the perimeter of the square? Express the perimeter with the appropriate units. *Hint* Hint 1: Definition of a perimeter *The perimeter of a square is the sum of the lengths of all four sides of the square.*

perimeter = Value| Units 12*4= 48 Answer is 48 m

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? 1. Use the available hints. 2. Guess Randomly and hope for some useful feedback 3. request the solution immediately

1. Use the available hints.

Suppose you are asked to find the area of a rectangle that is 2.1-cmcm wide by 5.6-cmcm long. Your calculator answer would be 11.76 cm2cm2. 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.

12 cm^2

Enter the expression 147N+α where α is the lowercase Greek letter alpha. Express your answer as a chemical expression.

14/7 N+ a

You can enter units that are combinations of units with prefixes. However, you must maintain the same unit system given in the problem. For example, this question uses the SI unit system. Therefore an answer in U.S. customary units, such as miles per hour would not be accepted as correct. A car traveling with constant speed travels 150 kmkm in 7200 ss. What is the speed of the car? Express the speed with the appropriate units. Hint: The equation for computing speed Enter your answer using units of force. The weight of the object is m⋅g=98 kg⋅m/s2m⋅g=98 kg⋅m/s2. Because 1 kg⋅m/s2 = 1 N1 kg⋅m/s2 = 1 N (1 newton), you can also express the answer as 98 N, in scientific notation as 9.8×101 N9.8×101 N, or with a prefix as 0.098 kN.

2.1*10-2 km/s

Enter the chemical equation 2H+(aq)+S2−(aq)→H2S(g) Express your answer as a chemical equation.

2H+(aq)+S2−(aq)→H2S(g)2H+(aq)+S2−(aq)→H2S(g) Careful to put the superscripts and subscripts in the proper locations

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 mm and a width of 12.0 mm. 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. *HINT* Hint 1: How to find the perimeter *The perimeter of a two-dimensional shape is the distance around the outside edge of the shape. In the case of a rectangle, there are two sides of length LLL and two sides of width WWW. Therefore, if you were to walk around the outside of a rectangle, you would walk a distance of 2L+2W2L+2W or 2(L+W)2(L+W).* Hint 2: How to find the area *The area AAA of a rectangle is given by the product of its length LLL and width WWW: A=L⋅W*

35.0,66.0 (it must be wrote like this with three figures and a comma directly between. No spaces)

When numbers are very small or very large, it is convenient to either express the value in scientific notation and/or by using a prefix with the unit. A pain-relieving pill has a mass of 0.005 gg. Express the pill's mass in grams using scientific notation or in milligrams. Express your answer in scientific notation to one significant figure or use a prefix on the unit. Hint Hint 1* Hot to interpret the prefix milli *The prefix mm (milli) implies multiplication by 10−310−3; thus, a milligram is 1×10−3 g1×10−3 g.*

5*10^-3 g

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

78 cm^3

You've just solved a problem and the answer is the mass of an electron, me=9.11×10−31kilogramsme=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. View Available Hint(s) *Hint 1 * Multiplication and superscripts You may use the scientific notation template to enter your answer, or type the following: 9.11*10^-31. The keyboard multiplication symbol * (Shift + 8) will appear as a multiplication dot, and the carat symbol ^ (Shift + 6) will allow superscript. Another way to get an exponent is by clicking in the menu.

9.11*10-31

Which of the following describes a growth mindset, as opposed to a fixed mindset?

All of the above phrases describe the growth mindset

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: 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. B: The only way to lose additional partial credit on a hint is by using the "Request Answer" button or entering incorrect answers. Leaving the question blank will not cost you any credit. C: 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. D: None of the above.

Answer: A, B, C

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: Submit your answer and then adjust it according to any feedback you receive. B: Return to the question after you've spoken with an instructor or classmate. C: Check for any hints that address the part of the calculation you're unsure about. D: None of the above.

Answers A, B, and C.

How do students with a growth mindset see their mistakes?

As opportunities to learn and improve their brain

Enter the molecular formula for butane, C4H10 Express your answer as a chemical formula. Entering more complex expressions To enter an ion such as SO42−use a subscript followed by a superscript. In general, use the stacked super/subscript only for entering an isotope. Do not use it for adding a single subscript or superscript. For example, when entering H+ you should see H+, not H+ with a subscript blank .

C4H10 (With 4 and 10 as subscript)

Overview Lewis When an assignment question requires that you answer by drawing molecules or species, you will see one of two similar canvases with buttons for bonds, electrons, charges, and atoms. The first is used most often with Lewis structures, and has menus such as the sample shown: To draw atoms, select an atom from the menu at the bottom, or click the button with the word More to access the periodic table. The carbon atom is active by default. Active buttons are highlighted in blue. Click anywhere within the grid area to create single atoms. To draw types of bonds, click a bond button on the left. Active buttons are highlighted, such as this single bond . You may draw a bond in one of two ways. You may click within the grid to create two atoms connected with a bond. Or, if the atoms already exist in the grid, you can connect them with a bond by clicking on one of the atoms and dragging your mouse over to the second atom. Click the bond button to deselect it and draw single atoms. To change the type of bond already drawn, click on the single bond button , and then click on the existing bond to rotate through single, double, and triple bonds. To place electron-dot pairs or single electrons, click for a lone pair or for a single electron, and then click on an atom already in the workspace. To place brackets around a polyatomic ion, click , and then click on the molecule. To edit a charge associated with an atom or polyatomic ion, click to increase the charge or to decrease the charge, and then click on the atom or bracket. You should see a charge appear next to the atom or to the upper right of a bracket. Click to change the charge sequentially, or type in the correct charge. To select and move atoms or bonds, click and then click the atom or bond you wish to move. The atom or bond will be highlighted in blue when selected. Then drag the atom or bond to a new location. To deselect a button, click the button to toggle on and off. An atom must be selected while drawing. To delete a portion of the molecule or ion, click and then click the element you want to delete. Deleting an atom will also delete the corresponding bond. For help while drawing molecules and ions, click .

Each question will specify whether lone pairs of electrons and charges are required. In general, you should draw all hydrogen atoms. Although the molecule or ion you draw must contain the correct atoms and bond structure, the orientation of the molecule or ion is not graded. Try drawing a molecule upside down and you'll see!

Complete the sentences by matching the names of trees to the appropriate blanks. To do this, drag the names on the left into the appropriate blanks in the sentences on the right. Match the words in the left column to the appropriate blanks in the sentences on the right. Terms may be used more than once. Make certain you have filled every blank with a term before clicking Submit. 1. Evergreens are plants that maintain their leaves in all seasons and include trees such as_______ , _______ , and _______ . 2. Hardwoods reproduce using flowers and have broad leaves; hardwoods include trees such as _______ ,_______ , and _______. 3. Deciduous trees lose their leaves seasonally and include trees such as __________ and __________. 4. Conifer leaves are generally thin and needle-like, while seeds are contained in cones. Conifers include __________and ________. Options: Pine Maple Mango Cedar Elm

Evergreens: Mango, Cedar Hardwoods: Mango, Maple, Elm Deciduous: Elm, Maple Confier: Pine, Cedar

Identify the continents by dragging the labels to the appropriate targets.

From Left to right North America South America Europe Antarctica Africa Australia Asia There will be an extra blank at the very top of the page. It is there to trick you.

Overview Sorting questions require you to place objects into different categories or bins. There will always be at least two bins and each bin is labeled according to the category it represents. An object can only belong to one bin. A bin can remain empty. Before an answer is submitted, it is possible to rearrange the objects by dragging them to new locations. To start over, click Reset. Once you're satisfied with your sorting, click Submit. Items to sort include: 1. Apple 2. Carrot 3. Avocado 4. Potato 5. Banana 5. Tomato

Fruits: Apple Banana Avocado Tomato Veggies: Potato Carrot

Which is NOT an element in developing expertise in a field?

Giving up

This one is a bit more complicated. Only because of the graphing options are a pain in the ass. Overview When an assignment question requires that you answer by plotting a graph, you will see the following buttons: To add a new graph, click . You will be prompted here to select a label. To add a straight line graph, select (currently this is the only graph type available). Then you can add points by clicking in the drawing area. To stop adding points on a graph, select or press the Escape key. At this point, your graph may be complete, although you have the option if you wish to further edit your graph as well. To move the points or position of your graph: Using your mouse: To move a point, click to select the point and then drag it to the new location. Actively selected points and graphs are highlighted. Alternatively, you may use the attributes panel on the left hand side to manually adjust the x and y coordinates of individual points. To move the entire graph to a new location, click between points on the graph and then drag. Clicking any empty area of the workspace will deselect whatever is highlighted.Using your keyboard: With a point or graph selected, press any arrow key to reposition. To add further points: If you wish to add additional points to your graph, click your graph and select (note that this button toggles between add and stop adding points). Then you can add points by clicking in the drawing area as before. To delete a selected point or graph, click . To delete using your keyboard, press Delete after selecting a point or selecting a graph. To change the graph label for the active graph, select the desired label from the drop-down menu below "Label". To clear your current graph from the drawing area (restart), select . There is a brief tips tour that summarizes the above information, which you can launch by selecting . For further help with graphing, select . QUESTION: Create a graph of y=2x−6y=2x−6. Construct a graph corresponding to the linear equation y=2x−6y=2x−6. *Hint* Hint 1: Identify a point to graph *You need to create a plot of y=2x−6y=2x−6.To identify points on this graph you must solve for the values of yyy when xxx takes on different values. What is yyy when x=5x=5?* Express your answer numerically. Answer is 4.

If the equation is y=2x-6 Assign x a number. Ex: what is y when x = 5. y=2(5)-6 simplified to y=10-6 so y=4 So you plot x at 5 and y at 4 Now to complete the graph, you need to solve for x at a different number. I chose 4. y=2(4)-6 y=8-6 y=2 Therefore x=4 y=2 Now you plot those on the graph and you have completed the formula. You don't have to use those numbers for the second one. it's up to you which numbers you chose.

This exercise is not intended to test your knowledge of any specific subject material. Therefore, on this question you will not be penalized for submitting incorrect answers. Vocabulary (sentence completion) exercises require you to drag terms in the left-hand column to the appropriate blanks, which look like boxes, in the sentences or paragraph on the right. When dragging a term over to a blank, be sure to note when the blank turns from gray to pale yellow; this change in color tells you that you have placed the term in the blank properly. The term may "snap back" to the left-hand column if you haven't placed it fully in the blank. Do not leave any blanks empty. For some sentences, you will have to fill more than one blank. In some exercises, you can use a word more than once. Other times, there may be more words than there are blanks; in this situation, you will not have to use every term. To start a vocabulary (sentence completion) exercise over, click Reset. Before you submit your answers, you can rearrange the terms by dragging them to new locations. When you are satisfied with your answers, click Submit.

Instructions Only

Why is the word "yet" powerful in developing a growth mindset?

It encourages you to continue along your learning journey, as you have not yet reached the final destination. Submit

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?

Key words to look out for: 1/(n-1) and also that there are 5 multiple choice questions. Meaning n=5 1/(n-1)= 1/(5-1) = 1/4 = 25% So the answer is 25%

What is neuroplasticity?

The ability to make new and stronger connections between the neurons in our brain as we learn

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 receive feedback as a reminder. 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. *HINTS* How to complete the sum Hint 1: *Recall that the sum of two numbers is the result you obtain by adding the two numbers together.* 9260+3240= 12500

The answer is 12500 *Hint* DO NOT ENTER COMMAS OR IT WILL COUNT AS WRONG

Would an answer that generated the response below be considered correct and give you full credit?

Yes

You can also enter units that are combinations of other units. Keep in mind that you have to indicate the multiplication of units explicitly either with a multiplication dot or a dash. You can add a multiplication dot by selecting the dot from the Templates menu. The weight of an object is the product of its mass, mmm, and the acceleration of gravity, ggg (where g=9.8 m/s2g=9.8 m/s2). If an object's mass is m=10. kgm=10. kg, what is its weight? Express the weight with the appropriate units. *HINT 1* The units for weight To calculate the weight of an object, you must multiply its mass by the acceleration due to gravity: weight = mass of object ⋅ acceleration due to gravityweight = mass of object ⋅ acceleration due to gravity Because you are multiplying a value with the units kgkg by a value with the units m/s2m/s2, find the resulting units by multiplying both units together: (kg)⋅(m/s2) = kg⋅m/s2

m*g = 98 kg *m/s^2 Because 1 kg⋅m/s2 = 1 N1 kg⋅m/s2 = 1 N (1 newton), you can also express the answer as 98 N, in scientific notation as 9.8×101 N9.8×101 N, or with a prefix as 0.098 kN. Answer is 98 kg*m/s^2

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 View Available Hint(s) link underneath the question statement for this part. Clicking this link will open up a list of clickable hints that will guide you to the correct number. (Random picture of a piece of paper in a hat) *Hint* Hint 1: Different types of hints and their impact on grading Hint 2: How to approach the problem Hint 3: What is x? Breakdown of the Hints: *Hint 1* Notice that there are three hints for this question. You are not required to use all of the hints or to use them in order. Each hint has a tagline that describes its contents. Based on the tagline you can decide whether or not a particular hint will be useful to you. There are two kinds of hints. Some hints, such as Hint 2 below, just provide you with information. Other hints, such as Hint 3 below, give you an opportunity to answer a simpler question that is related to the main question you are solving. These hints either have questions in the tagline or tell you to do something (e.g., Find..., Determine..., Identify..., etc.). There are two ways that this type of hint can help you: Answering the simpler question gives you a chance to check that you are on the right track. If you correctly answer the simpler question, you will receive partial credit for the part even if you are unable to answer the main question. Your instructor may choose to give you a bonus for not using hints or to deduct a small penalty for using hints. If you are stuck, using the hints will usually result in a higher score than simply trying to guess because you may lose fewer points for opening a hint than for getting the answer to the main question incorrect. There is a more detailed explanation of how hints are graded in the help available by clicking the Help link at the top right corner of your screen in the main Mastering window. In this problem, however, you will not lose any credit for using the hints. Now, open up the second hint for some help finding the magic number. Breakdown of Hint 2: Although you could try to guess the magic number you would most likely exhaust your tries before getting the correct answer. To help you, the magic number is equal to 15×x15×x, where xxx is a number between 1 and 10. magic number=15×x Breakdown of Hint 3* Recall that the previous hint stated that the magic number is equal to 15×x15×x, magic number=15×xmagic number=15×x where xxx is a number between 1 and 10. Specifically xxx is an even number between 1 and 10. Try to guess the value of xxx. You may submit as many guesses as you need. Enter each guess into the answer box that follows.

x=4


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