unit 1- scientific processes, measurement, and calculation
0.000197 km into mm
197 mm
how many sig figs in 0.023 g
2
951.08g + 9.018g + 0.00038111g (apply rule- include units)
960.10 g (line above 0) or 9.6010e2 g
(8.50cm + 5cm) * 3.0 cm
= 14 cm * 3.0 cm = 42 cm^2
when recording a measurement of a ruler/graduated cylinder etc...
record all the numbers that are certain and one that is a guess
when recording a measurement of a digital scale...
record all the numbers that are certain, do not estimate last digit
0.0085cm * 0.000875cm * 0.0850cm (apply rule- include units)
0.000 000 63 cm^3
0.00871g / 12.5 L (apply rule- include units)
0.000 697 g/L
25.1 g into kg
0.0251 kg
37 mL into L
0.037 L
0.00121 km into dam
0.121 dam
0.038g + 0.0975g + 0.0870g (apply rule- include units)
0.223 g
23.08 dL into daL
0.2308 daL
how many sig figs in 0.000 000 000 008 mg
1
how many sig figs in 0.01 L
1
five sig fig rules
1. all nonzero numbers are always significant 2. sandwiched zeros are always significant 3. leading zeros are *never* significant 4. trailing zeros are only significant if there is a decimal point 5. counting numbers and conversion factors have infinite sig figs
853m / 0.0785 sec (apply rule- include units)
10 900 m/s
123 hm into mm
12 300 000 mm
120 L + 0.05 L + 10.8 L (apply rule- include units)
131 L
15.987 g - 1.75 g (apply rule- include units)
14.24 g
estimate length of line (flip and hide bottom)
17.31 cm (estimate till hundredth)
how many sig figs in 1.7e5 mm
2
2.54 Mm into km
2 540 km
0.2005 m into cm
20.05 cm
2.5m * 8.53m (apply rule- include units)
21 m^2
0.213 dL into mL
21.3 mL
26.2 km into m
26 200 m
how many sig figs in 0.00000123 g
3
how many sig figs in 0.0908 mg
3
how many sig figs in 23 500 mL
3
how many sig figs in 9030 s
3
how many sig figs in 1.70e-4 L
3 (0.000*170*)
32.7 mg into cg
3.27 cg
estimate length of pencil (flip and hide bottom)
3.78 cm (estimate till hundredth)
98.05 km * 3.88 km (apply rule- include units)
380 km^2 (line above 0) or 3.80e2 km^2
how many sig figs in 0.02001 L
4
how many sig figs in 18.00 mL
4
how many sig figs in 3.500 L
4
estimate measurement in graduated cylinder (flip and hide bottom)
43.1 mL (estimate till tenth- read from bottom of meniscus)
how many sig figs in 23500. g
5
3.08m + 2.0841m + 0.0015m (apply rule- include units)
5.17 m
200 L + 338 L + 2.10 L
540 L
561000 μL into mL
561 mL
0.0579 dag into mg
579 mg
estimate measurement in graduated cylinder (flip and hide bottom)
6.32 mL (estimate till hundredth- read from bottom of meniscus)
6.99 hL into cL
69 900 cL
891 g into hg
8.91 hg
80.3 kg into grams
80 300 g
What is the volume of a box that measures 10.5 mm by 25.0 mm by 35.5 mm? (apply rule- include units)
9320 mm^3
if 15.0 mL of acetone has a mass of 11.76 g and 15.0 g of carbon tetrachloride has a volume of 9.47 mL, which substance is more dense?
acetone: 11.76 / 15.0 = 0.784 g/mL carbon tetrachloride: 15.0 / 9.47 = 1.58 g/mL carbon tetrachloride is more dense
mass of rock = 10.7 g water displacement: 23.9 mL initially, 25.7 after rock calculate density
d = m/v = 10.7 / (25.7 - 23.9) = 10.7 / 1.8 = 5.94 = 5.9 g/mL or *5.9 g/cm3* (round to 2 sig figs)
estimate volume of metal tube and ring (flip and hide bottom)
estimate till tenth 1. 28.9 mL - 18.8 mL = 10.1 mL 2. 67.8 mL - 64.0 mL = 3.8 mL
metric system prefixes (with abbreviation
giga- G mega- M kilo- k hecto- h deka- da deci- d centi- c milli- m micro- μ nano- n
how many sig figs in 1 m = 100 cm
infinite- exact number, not estimated
how many sig figs in 12 pencils
infinite- exact number, not estimated
if the density of an object is 8.37 g/mL, what is the mass of 2.97 mL?
m = dv = 8.37 * 2.97 = 24.9 mL (3 sig figs)
formula for density
mass/volume
addition and subtraction sig figs
round answer to the amount of decimal places the number with least number of *decimal places* has ex: 2.306 + 1.2 = 3.506 = 3.5
multiplication and division sig figs
round answer to the amount of sig figs the number with the least number of *sig figs* has ex: 2.305 * 1.4 = 3.227 = 3.2
