11 - Measurement and Data Processing

Question 1

qualitative data

Answer 1

non-numerical data

Question 2

quantitative data

Answer 2

data obtained from measurements

Question 3

random error

Answer 3

uncertainties associated with the apparatus used to make measurements and by human limitations such as reactions times and cannot be eliminated

Question 4

systematic error

Answer 4

faults in procedure and experimental design that cause a deviation (in all results) in a particular direction

Question 5

precision

Answer 5

closeness of agreement between different test values (in repeats)

Question 6

accuracy

Answer 6

closeness in agreement to the actual literature value

Question 7

independent variable

Answer 7

changed in a controlled way

Question 8

dependant variable

Answer 8

the variable tested and measured - it is dependent of the independent variable

Question 9

sketched graph

Answer 9

used to depict trends between variables that are proportional or inversely proportional. they do not have scaled axis

Question 10

drawn graphs

Answer 10

used to depict qualitative measurements and trends from data and have scales, units, line of best fit, title, etc

Question 11

interpolation

Answer 11

determining the unknown value within the limits of the values already measured

Question 12

exrapolation

Answer 12

determine value that lies outside of the range of values measured

Question 13

index of hydrogen deficiency (IHD)

Answer 13

determine the amount of rings or multiple bonds in a molecule. IHD = (2x-2-y)/2

Question 14

Mass Spectrometry

Answer 14

mass of parent molecular ion and also its fragments

Question 15

Infrared Spectroscopy

Answer 15

looks at transmission of light through bonds due to the frequency they vibrate. 0% transition means all light is absorbed

Question 16

Proton nuclear magnetic resonance spectroscopy (H NMR)

Answer 16

uses radio waves and is composed of peaks with splitting due to the number of hydrogen environments and the hydrogens on neighbouring carbon environments. Teramethysilale is the standard as it requires the most magnetic force do to the non polar nature, electrons are relatively closer to hydrogen than in electronegative compounds.

Question 17

x-ray crystallography

Answer 17

uses x-ray (same wavelength as atoms and allows a 3’d image of the molecule including bond lengths and angles