Significant Figures, Units, Conversions, Density Keep your brains on and your calculators alert!

Significant Figure Rules Nonzero integers are significant Leading zeros are never significant Captive zeros are always significant Trailing zeros are only significant when there is a decimal present in the number Exact numbers have an infinite number of significant figures

Significant Figures x 10 5

Significant Figure Rules for Addition and Subtraction The answer has the same number of decimal places as the least precise measurement = =

Significant Figure Rules for Multiplication and Division The number of SF in the answer can be no greater than the number of SF in value with the least number of SF. 7.2 x = ÷ 1 =

Temperature Conversions Fahrenheit to Celsius: (  F  32  F) x 5  C / 9  F Celsius to Fahrenheit: (  C x 9  F / 5  C) + 32  F

Temperature Conversions Celsius to Kelvin:  C Kelvin to Celsius: K  273

How many SF are in the following: a b c x d.2007 e. 6 x 10 5 f.47,000 g h

a b c x d.2007 e. 6 x 10 5 f.47,000 g h Round the following to 3 SF:

Perform the following using applicable SF rules: a b. 12  c. (8.040 x ) x (9 x 10 6 ) d. 400  3.5

Measurement mass--kg length--m time--s temperature--K amount of substance--mol

Measurement Prefixes giga(G)– mega(M)—10 -6 kilo(k)– hecto(h)– deka(da)– deci(d) centi(c) milli(m) micro(µ) nano(n)

Accuracy Precision Random error Systematic error

Metric-Metric Conversions 360 mm = _____m 4.25 x 10 −5 ML = _____mL 325 mg = _____kg

Metric-English Conversions 360 mm = _____in 4.25 x 10 −5 ML = _____gal 325 mg = _____lb 100 m/s = _____mi/h

Density D = mass/volume V rectangular prism = l x w x h V cylinder = πr 2 h V sphere = (4/3)πr 3

Density A square piece of cobalt glass (glass with cobalt ions mixed into it) has a mass of g. Its dimensions are 50 mm x50 mm x 2 mm. What is its density in g/cm 3 ?

Density A cylindrical piece of aluminum metal has a diameter of 12.5 mm and a mass of g. The density of aluminum is known to be 2.70 g/cm 3. What is its length in mm?

Density A steel solid sphere has a diameter of 70 cm. The density of this steel is known to be 7.80 g/cm 3. What is its mass in g?