Download SCIE 0900 Winter 2009 REVIEW FOR TEST 1

SCIE 0900 Winter 2009
REVIEW FOR TEST 1
For the test and/or lab practical be sure to understand and know how to do everything on this
review sheet. Plan to able to show your work.
~Safety – review safety rules of the lab
~Lab equipment - what you used in lab (balances, glassware, etc…
~Measuring - Metric units - know what they are for volume, length, mass, temperature
Giving answers in correct sig figs (digits)
Terms to know:
Least common denominator
Volume
Accuracy
Absolute Value
Precision
Significant figures
Displacement
Exact Numbers
Meniscus
Uncertainty in a measurement
Interpolation
Parts of a measurement
Extrapolation
Metric System
Base Units and what are they
SI Units
Parts of a measurement
Based on powers of 10
Positive and negative numbers:
Adding and Subtracting
(+4) + (+2) = (+6)
(+4) – (+2) = (+2)
(-4) + (-2) = (-6)
(-4) - (-2) = (-2)
(+4) x (+4) = (+16)
(-4) + (+2) = (-2)
(-4) – (+2) = (-6)
(+4) x (-4) = (-16) [same for dividing]
Do the following problems:
Add these numbers:
+5, -7, -3 =
Subtract these numbers:
-10- (-5) =
Multiply or divide these numbers: (-15) x (2) =
+10, -3, -3 =
13- ( -6) =
(-30) ÷ (-6) =
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Fractions:
Numerator
Denominator
Adding and Subtracting – denominators must be the same
1/3 + 1/5 =
5/15 + 3/15 = 8/15
Multiplying:
2/3 x ¼ = 2 x 1 = 2 = 1
3 x 4 12 6
½ X 5/8 =
Dividing:
3/5 ÷ ½ = 3 x 2
5 x 1
= 6
5
½ ÷ 5/8=
Decimals – Adding, subtracting, multiplication and division
- Know how to do all of these
5.345g +16.211g =
49.342mL - 21.21 mL=
39.36L ÷ 3=
5.00 g X 25 =
Ratios and Proportions
What is a ratio?
• comparison of two numbers using a fraction
• Expresses the relative size of two quantities as the quotient of one divided by the other
• The order in which the ratio is written defines the comparison
Written in 3 ways:
a:b
or
a/b
or
a to b
•
•
•
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What is a proportion?
• A statement that two ratios are equal.
• A comparison of one fraction to another.
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When two ratios are equal, then the cross products of the ratios are equal.
That is, for the proportion, a:b = c:d , a x d = b x c
Solving for X in a proportion:
Solve the variable by writing a proportion. Then solve
the proportion.
6 bottles in 3 cases.
z bottles in 8 cases.
Significant Figures (Digits) - what are they, how to count them
All the digits known with certainty, plus one estimated digit
Rules:
1. Non-Zero integers - Always count at significant figures (2457 L)
2. Leading zeros - The first significant figure in a measurement is the first digit other than zero counting
from left to right (0.0045g)
3. Captive zeros - Zeros within a number are always significant (30.0809 g)
4. Trailing zeros – at the end of numbers (4.50 g has 3 sig. digits) (100 m has 1 sig. digit)
0nly significant if a number contains decimals
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Determine the number of significant figures in the following numbers
19.003=
100.2 =
3.0 =
60.55321=
0.0005=
1500. =
1500 =
0.4400 =
2006 =
Rounding Sig Figs - Only use the first number to the right of the last significant digit
Round to 2 significant figures
Round to 3 significant figures
18.89 =
18.89 =
2,292 =
2,292 =
0.0006749 =
0.0006749 =
Conversions - know how to set and solve using a direct proportion
1. 9 inches = _______ cm
2. 7 pounds = _____ ounces
2.54 cm = 1 inch
16 ounces = 1 pound
3. Bob can type 3 pages in 18 minutes. How many pages can Bob type in 33 minutes?
4. If a heart beats 98 times per minute, then how many times does it beat in an hour?
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Math Based Problems Review –
Be prepared to do problems similar to these below and those from the homework assignments.
1. You are a worker (A) in a pen factory. If you can assemble 22 pens in three minutes. How many pens can
you assemble in a 50 minute period?
2. You are another worker (B) in the pen factory. You can assemble 14 pens in two minutes. How long
will it take you to assemble 75 pens?
3.
Which worker is most efficient, A or B?
Graphing Review – Know all the parts of the graph:
Dependent variable
Independent variable
Best Fit Line
X – axis
Y - axis
Title
Legend/Key
Insects Killed pe r Trap
50
45
Nu m b er of Ins e cts Kille d
40
35
30
Moths
25
Beetles
20
15
10
5
0
0
5
10
15
20
25
Am o unt of Pe s ticide pe r T rap (g )
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