Question 1 (10 points) A student collected the data presented in table 1. To collect the data presented in table 1, a student first weighed an empty graduated cylinder. The student then added 1.0 mL of an unknown liquid to the graduated cylinder and then obtained the mass on a balance. Next, the student filled the graduated cylinder to 2.0 mL and again obtained the mass. This process was repeated up to 10.0 mL of the liquid. Table 1. Mass and volume values of mass and volume of an unknown liquid Mass (g) Volume (mL) 8.5 0.00 9.5 1.00 10.6 2.00 11.9 3.00 13.1 4.00 14.2 5.00 15.1 6.00 16.3 7.00 17.2 8.00 18.5 9.00 19.6 10.00 You will need to graph the points in table 1 following the graphing directions below. Graphing Directions Graph paper can be found here. A line graph can be used to express the relationship between two quantities, which can be referred to as X and Y. Step 1. Determine which variable is X and Y. The variable X is to be plotted on X-axis (horizontal axis), also called the abscissa. The variable Y is to be plotted on the Y-axis (vertical axis), and it also known as the ordinate. Most of the time, one variable is under the experimenter's control, the independent variable (x-axis), and the other variable is the quantity measured by the experimenter is called the dependent variable (y axis). Step 2. Determine the scale for each axis.
Step 3. Place labels and units on the axes to show what is being plotted. E.g. Temperature (°C) Step 4. Plot the data and use symbols that will be easily seen when a line is drawn through them. Step 5. Draw a linear line through the data points. This is called a trend line. These factors should be considered: a. Omit obviously inaccurate points. b. All points may not be exactly on the line, thus draw an average line (approximately equal points above and below the line). c. Do not connect dots and use a straight edge. Step 6. Determination of the Equation of the Line. a. Pick two points on the trend line to find the slope. For example: (X₁, Y₁) and (X2,Y₂). Indicate which points on the line you are using by circling them on your graph. NOTE: The points should NOT be data points. They MUST be points that are on the line you have drawn. Look for places your line cleanly crosses the graph lines. Solve for slope by plugging those points into m = (Y2-Y 1)/(x2-x1). b. The y-intercept is the point at which your line crosses the y-axis. This is b in the equation of the line. c. Write the equation of the line on your graph inserting m and b as you calculated above. Include the units of m and b in your equation. The value of the slope is the density value of the unknown liquid. y = mx + b Step 7. Place an appropriate title at the top of your graph. Be sure it is descriptive and is more than "this vs. that." Hints on manual graphing: 1. Use the full page available (or as much as possible). 2. Looking at your data, decide what range needs to be covered on each axis and have the axis cover those values only. 3. You do not need to start at 0. 4. Select a convenient increment. Each square in the graphing paper should be defined as an exact amount! For example, if you select increments of 0.50, each square measures 0.50 and the avis will look like this:
3. You do not need to start at 0. 4. Select a convenient increment. Each square in the graphing paper should be defined as an exact amount! For example, if you select increments of 0.50, each square measures 0.50 and the axis will look like this: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 5.00 5. Label each axis with the unit. 6. Experimental points should be clearly marked on the graph. They should be visible even after the line has been drawn. Once you have your graph ready, submit a picture of the graph as a response. Make sure to label the axis and to draw the best fit of the line. Also, include the equation of the line (Step 6). You can find the rubric for the graph evaluation here.
Question 2 (2 points) Using the density value obtained from your graph submitted in question 1, along with the known densities provided in table 2, select the identify of the unknown liquid. Table 2. Density values for different liquids Liquid Density (g/mL) Isopropyl alcohol 0.786 Mineral oil 0.830 Hydrogen peroxide 1.110 Chloroform 1.488 Mineral oil Chloroform Isopropyl alcohol Hydrogen peroxide
Question 3 (3 points) A student decided to observe the relationship between the density of different substances and the ability of the substance to float or sink. The video below shows the student experiment. 0:05 / 1:17 Based on the experimental observations presented on the video, explain the relationship between the ability of a substance to sink or float and the given density values for each substance. Using the density values given in the table below, explain which substance(s) will float or sink on water. Density values for generic substances Substance Density (g/mL) 1.28 0.85 2.70 0.79 ABCO А с
Question 1 (10 points) A student collected the data presented in table 1. To collect the data presented in table 1, a st
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