Chem-is-Try AD Units 1 & 2 Final Exam Review Fall 2012 thatonerule: #2135 Your desire for success is aspiration, actually doing something about it is perspiratio n.

If you will miss the exam…  In the auditorium on Monday Jan. 7.  May schedule with me to take the exams Tuesday or Wednesday (Jan.8- Jan.9) after the break. FIRST DAY December 18 12:30 – 2:30 6th PERIOD EXAM Review 1 st – 5 th period SECOND DAY December 19 7:30 – 9:302nd PERIOD EXAM 9:40 – 11:404th PERIOD EXAM 5 th and 7 th period reviews THIRD DAYDecember 20 7:30 – 9:303rd PERIOD EXAM 9:40 – 11:455th PERIOD EXAM FOURTH DAYDecember 21 7:30 - 9:30 1st PERIOD EXAM 9: :457th PERIOD EXAM

Qualitative v. Quantitative Data  Qualitative → Quality  Data can be observed but not measured; descriptions  Colors, textures, smells, tastes, appearance, beauty, etc.  Quantitative → Quantity  Data can be measured; numbers  Length, area, volume, weight, speed, time, temperature, cost, members, ages, etc.

 Concept of metric units and when to use  Metric prefixes based on powers of ten, so it’s easy to convert between units.  Remember:KING HENRY DIED BY DRINKING CHOCOLATE MILK

Kilo Hecto Deka BASE Deci Centi Milli Left = /10 Right = x10 How to use

 Density (gizmo) D=m/V Volume by displacement

Scientific Notation  This is an easy way to express really large or really small numbers conveniently. The general format for numbers expressed this way is some number x 10 some power

Try It! Express in scientific notation: a)61,500 b) c)321 d)64,960,000 e) Express in standard notation: x x x x 10 -4

Accuracy and Precision  Accuracy: how close a measurement is to the true value (the “correct answer”)  Precision: how close a value is to other values in that series

Are the following groups of measurements accurate, precise, both, or neither? 1) Given: true mass of sample of zinc is 14.5 g Measurements made: 13.2 g, 15.6 g, 17.9 g, 12.0 g 2)Given: true volume of sample of water is 33.3mL Measurements made: 22.4 mL, 22.2 mL, 22.4 mL, 22.3 mL 3) Given: true length of copper wire is 58.5 cm Measurements made: 58.4 cm, 58.5 cm, 58.5 cm, 58.4 cm

Significant Figures – Atlantic/Pacific Rule  If the decimal point is present, start counting digits from the Pacific (left) side, starting with the first non-zero digit.  If the decimal point is absent, start counting digits from the Atlantic (right) side, starting with the first non-zero digit. Present Absent

Try It: How many sig figs? a) b)2.50 c)2500 d)3.7 x 10 9 e)45009 f)100. g) h) i)100 a)3 b)3 c)2 d)2 e)5 f)3 g)7 h)3 i)1

Addition/Subtraction  Calculated value cannot be more precise than the least precise quantity used in the calculation.  The least precise has the fewest digits to the right of the decimal point.  calculated value will have the same number of digits to the right of the decimal point as the least precise quantity. Example m m + 12 m m BUT report as 49 meters.

Try It! a) g g b) cm – 6.50 cm a)0.201 report as 0.20 g b) report as cm

Multiplication/Division  The number of significant figures in the final calculated value will be the same as that of the quantity with the fewest number of sig figs used in the calculation. Example  15/3.155= but is reported as 4.8 (2 sig figs)  5.60 x = reported as 39.8 (3 sig figs)

Try It! a)7846 X X X 3300= b) ÷ 83= c)(57.6 X 3) ÷ (34 X 3.00 X )= d)(6.10 X 107 ) + (3 X 107 )= a) or 5.6 X b)7.0 c)0.02 d)9 X 10 7

Dimensional Analysis  Find a relationship (or set of relationships) between units  Cancel out units until only desired units are left  Then do the math  Given: Unit #1  Desired: Unit #2 Unit #1 Unit #2

Try It! Important Conversion Factors 60 seconds = 1 minute 60 minutes = 1 hour 1 mile = 5280 feet 1 foot = 12 inches 2.54 centimeters = 1 inch 100 centimeters = 1 meter 1. How many centimeters are in 6.00 inches? 2. If it takes 2.5 minutes to complete a task, what is that same length of time in seconds? 3. Express 24.0 cm in inches. 4. If a container of water absorbs 3.4 cal of heat, what is the amount of energy absorbed (in joules)? 5. How many seconds are in 2.0 years?