Here are mass spectrometric signals for methane in H2: CH4 (vol%): 0 0.062 0.122 0.245 0.486 0.971 1.921 Signal (mV): 9.1 47.5 95.6 193.8 387.5 812.5 1 671.9 (a) Subtract the blank value (9.1) from all other values. Then use the method of least squares to find the slope and intercept and their uncertainties. Construct a calibration curve. (b) Replicate measurements of an unknown gave 152.1, 154.9, 153.9, and 155.1 mV, and a blank gave 8.2, 9.4, 10.6, and 7.8 mV. Subtract the average blank from the average unknown to find the average corrected signal for the unknown. (c) Find the concentration of the unknown and its uncertainty.
October 13, 2016 Thursday, October 13:48 PM Compounds of row elements and lower can have expanded octets. Chapter 4 Page 1 Chapter 4 Page 2 Electronegativity is an atom’s ability to attract electrons to itself. Electron density maps are useful in showing where electrons tend to spend the majority of their time (red) Chapter 4 Page 3 tend to spend the majority of their time (red) • A nonpolar covalent bond occurs between two nonmentals or a semimetal and a nonmetal whose E is less than 0.5 • A polar covalent bond occurs between two nonmentals or a semimetal and a nonmetal whose E is between 0.5 and 2.0 • An ionic bond is