Right tools for the right job Write down the names of these items found in the lab

Equipment and Measurement

Scientific Measurement Rules for measurement: all units must : All measurements must have a unit For example, yards or feet Be common It must be measured in unit that people know like feet Be common to everyone Places like Japan and Germany do not use our system of measurement, they use the metric system.

Right tools for the right job Measurement Tool Unit Length Meter Stick Meters Mass Balance Grams Volume Graduated Cylinder Liters Sometimes you will notice a meniscus: a curving of the surface of the liquid.

Two Systems We have two systems for measuring: International System (used all over the world) ex. Meter, grams US Customary System (mainly used in America) ex. Foot, inch How do they compare? 1 inch = 2.54 cm 1 lb = 0.453kg 3.281 feet = 1 meter 33.8 fl oz = 1 L 0.035 oz = 1 gm 1 gal = 3.78 L

Temperature SI unit for temp is Kelvin The metric is Celcius The English is Fahrenheit We can convert Celcius to Fahrenheit and to Kelvin 212 degrees F = 100 degrees C = 373.15 K This is the boiling point of water

Changing the Magnitude The Metric system or SI is based on units of 10. Prefix Kilo (k) Hecto (h) Deka (da) Base Unit Deci (d) Centi © Milli (m) Abbrevation Km kL kg Hm hL hg Dam daL dag Meter Liter gram Dm dL dg Cm cL cg mm mL mg Mulitplication Factor 1000 100 10 1 0.1 0.01 0.001

So how do I change units?? You multiply when changing from a larger unit to a smaller unit. And you divide when changing from a smaller unit to a larger unit. For example: If you have a bowling ball with a mass of 4.54 kg. If you wanted to convert it to grams, you would have to move 3 spaces on the table to the right. Each space represents a multiplication of 10. So 10 X 10 X 10 = 1000. So, you multiply by 1000. 4.54 kg X 1000 = 4540 g.

Another example A soda can has a volume of 355 mL and you want to convert it to dL. Move two places to the left, so 10 X 10= 100. You divide by 100. 355 mL/ 100= 3.55dL

Precision and Accuracy Accuracy: how correct a measurement is For example, if you measure a room as 16.7 feet but a blueprint of the room says it is 16.1, that would be inaccurate. Precision: how small a scale is being used to make a measurement . For example a measurement made to the nearest 1/8 of an inch is more precise than a measurement that is rounded to the nearest inch Estimate: a judgement