# measurement stuff for research

## Metric Conversions

The Great Man King Henry’s Daughter Drank Chocolate Milk Until Nine P.m. - tera, giga, mega, kilo, hecto, deca, deci, centi, milli, micro, nano, pico

tera- - T, 10^12

giga- - G, 10^9

mega- - M, 10^6

kilo- - k, 10^3

hecto- - h, 10^2

deca- - da, 10^1

deci- - d, 10^-1

centi- - c, 10^-2

milli- - m, 10^-3

micro- - μ, 10^-6

nano- - n, 10^-9

pico- - p, 10^-12

## Microscopes

40x = 2 boxes = 4 mm = 4000 μm

100x = 2 boxes/2.5 = 0.8 boxes = 1.6 mm = 1600 μm

400x = 2 boxes/10 = 0.2 boxes = 0.4 mm = 400 μm

take estimate of sample size (ex. 1/3)

multiply field of vision (ex. 400 μm or 400x) by sample size (1/3) = about 133.3 μm

## Volume

graduated cylinder - measures anything greater than 10 mL; types include 10 mL, 25 mL, 100 mL, 250 mL, 500 mL, and 1 L

serological pipette - measures anything less than or equal to 10 mL; types include 1 mL, 2 mL, 5 mL, and 10 mL; used with pumps (blue and green)

micropipette - types include P-10, P-20, P-100, P-200, and P-1000

P-10 - measures 0.5 μL to 10 μL; uses small white tips

P-20 - measures 2 μL to 20 μL; uses small white tips

P-100 - measures 10 μL to 100 μL; uses medium yellow tips

P-200 - measures from 20 μL to 200 μL; uses medium yellow tips

P-1000 - measures from 200 μL to 1000 μL or 1 mL; uses large blue tips

### Volume Practice

25 μL - P-100

10 μL - P-10

1 μL - P-10

1000 μL - P-1000

1 mL - P-1000

2 mL - 2 mL serological

175 μL - P-200

23.5 μL - P-100

6.5 mL - 10 mL serological

125 mL - 250 mL graduated cylinder

7 μL - P-10

2.87 mL - 5 mL serological

555μL - P-1000

## Mass

standard balance - measures solid mass over 900 mg; accurate up to the hundredth (0.01) of a gram

analytical balance - measures solid mass under 900 mg; accurate up to the thousandth (0.001) of a gram

### Mass Practice

2.0 g - standard balance

40 mg - analytical balance

30 g - standard balance

2.006 g - standard balance

3.5 g of salt - standard balance

6.5 mg of DNA - analytical balance

12.5 g of gelatin - standard balance

## Remember

1 cm^3 = 1 mL = 1 g

percent error equation - (observed mass - expected mass)/expected mass x 100

also know procedures for all measuring instruments (balances, micropipette, etc.)

### Random Practice

find the mass in grams

1000 μL - 1 g

500 μL - 0.0005 g

53 μL - 0.000053 g

13.7 μL - 0.0000137 g