Lecture 1 + 2

Question 1

hypothesis

Answer 1

a testable statement; falsifiable

Question 2

controlled variables

Answer 2

ideally don’t change, common to all treatments

Question 3

independent variables

Answer 3

what you are altering in the experiment

Question 4

dependent variable

Answer 4

what you are observing in the experiment; respond to changes in independent variable

Question 5

positive controls

Answer 5

an experimental treatment which will give the desired result

Question 6

negative controls

Answer 6

an experimental treatment which will not give desired results

Question 7

false positive

Answer 7

• shown by negative control

- something wrong with machine/sample

Question 8

false negative

Answer 8

shown by positive control

Question 9

single blind

Answer 9

one knows

Question 10

double blind

Answer 10

both don’t know

Question 11

causation

Answer 11

A caused B

Question 12

correlation

Answer 12

A + B, but there could be a C that affected things

Question 13

sensitivity

Answer 13

min. amount of X needed to record a positive result

Question 14

specificity

Answer 14

a positive result only comes from a truly positive sample

Question 15

random error

Answer 15

new error introduced with each measure (weather, temp)

Question 16

systematic error

Answer 16

error that is consistently present (machine)

Question 17

accuracy

Answer 17

how close to true value

Question 18

precision

Answer 18

how reliable; comparing to other measurements

Question 19

Realistically, any lab manipulations with have…………sig figs

Answer 19

2, maybe 3

Question 20

pH meter

Answer 20

• glass probe permeable to H+

- current by probe compared against standards to report a pH value

Question 21

scale

Answer 21

• to weigh chemicals

- must be tared/zeroed with empty container

Question 22

volumetric pipette

Answer 22

measure just one volume

Question 23

graduated pipette

Answer 23

lines along length

Question 24

some pipettes are ______, some arent

Answer 24

blow out

Question 25

micropipettes

Answer 25

volumes of 10 to to 0.0002mL, disposable tips, two stop-plunger

Question 26

1mL = ___ul

Answer 26

1000 microliter

Question 27

Dilution equation

Answer 27

c1v1=c2v2

Question 28

[H+][OH-]=

Answer 28

10^-14

Question 29

pH=

Answer 29

-log[H+]

Question 30

pKa

Answer 30

equal amounts of the acid and conjugate base

Question 31

A buffer pair is only effective …

Answer 31

+/- 1 pH unit from pKa