C125 Midterm Revision Questions and Answers

rearrange the ideal gas equation, PV=nRT to the form y=mx+b for the case where V is plotted on the y-axis and n on the x-axis. Name the equation, slope,a dn intercept - Answer- V= RT/P (n) slope: RT/P intercept: none Interpolation - Answer- estimating a value within the range of measured data extrapolation - Answer- projection; conjecture; V. extrapolate: infer (unknown information) from known information best fit line equation commonly takes y=mx+b format. What are your y, x, and b? - Answer- y = dependent variable (v) x = independent (n) m = slope (RT/P) b = intercept In assignment 2 (excel), students are asked to obtain the slope and intercept by rearranging the Ideal Gas Equation into y=mx+b format. The other way of achieving this goal is based on the definition of slope and y intercept. Y-intercept is where the line crosses the y-axis. In another word, it is the y-value when x=0. What is the y-intercept in assignment 2 based on this definition? - Answer- 0 In assignment 2 (excel), students are asked to obtain the slope and intercept by rearranging the Ideal Gas Equation into y=mx+b format. The other way of achieving this goal is based on the definition of slope and y intercept. The slope is defined by equation 2. When the y-intercept is 0, the slope is y/x. What is the slope in assignment 2 based on this information? Compare the slope and y-intercept obtained here to what you obtained in assignment 2. - Answer- RT/P They are the same In assignment 3 (excel), to obtain the density, which has to be the independent variable and hence be plotted on the x-axis? Which has to be the dependent variable? - Answer- independent variable = x = v (D=m/v, slope=y/x) How can the density be obtained from the graph (excel)? - Answer- Density can be found by looking at the slope