U1D4: Measurement in Science

Do Now: 1. place any Owed Work in folder 2. POGIL Qs out for collection 3. Read the following and come up with a hypothesis that may be being tested Copy and answer (4.5 min) A student wondered how doing their homework affected their grade in chemistry. To test it they did not do any of their homework and they failed the marking period. The next marking period they did their homework every night and got an A.

U1D4: Measurement in Science (3G) Do Now: 1. any signed safety and or guideline papers in folder 2. Safety Lab out for collection: WS, questions, paragraph: stapled 3.. Check your answers to Practice #1 (Keys are in the basket, next to the pens) Today: 1. Sci Method Check 2. Measurement notes 3. Measurement Lab

Day 4 Homework Read notes p. 5-7; outline/HL (Vocab def) Complete the lab Due: Day 7

Todays Goal: Become experts at using lab equipment to make precise and accurate measurements Today: 1. Measurement Notes 2. Measurement Lab 3.

So you think you can measure! Measurement is super important in any science and it needs to be done correctly and consistently

Science Measurements Measurement gives the universe meaning! How tall are you? How much do you weigh? How old are you? How fast can you run? How much volume do you displace? All of these questions are designed to give us reference to the world around us.

The Metric System In science we use the metric system, because it’s awesome – Why is it awesome? – Easy conversions!!

Why the metric system Rocks! Lets say you had to convert 2 miles to inches: – 2 miles x 5,280 feet/mile x 12 inches/foot =??? – 126,720 inches…cant do that in your head! Lets say you had to convert 2 kilometers to centimeters: – 2 km x 1000 m/km x 100 cm/m = – cm…could do that in your head All powers of 10!!

Metric Units (Reference Table D and C)

Rules 1) N3: No Naked Numbers. All measurements and answers to math problems must have units written after the numbers. 3 3 grams

Rules 2) No Work, No Credit. You must show all of the following when doing math problems: the equation you are going to use, the equation rearranged with numbers and units substituted in for all of the variables (numerical setup) the final answer, rounded properly with units after.

Rules ‘But what if I can do it all in my head?’ – You still have to show all of your work. – Womp womp – womp.

Measuring Instruments Balance: – Measures mass: amount of matter in an object – Unit: gram (g) – To use: Remember to zero before each use! Metric Ruler: – Measures distance (length, width, height) – Unit : centimeter (cm) – Make sure you line up the end of the object at zero!

Instruments continued.. Graduated cylinder: – Measures volume: amount of space an object takes up. – Unit: milliliter (mL) – Use: read the bottom of the meniscus at eye level! Thermometer: – -Measures the average kinetic energy of the molecules. – Unit: degree Celcius ( o C) – Use: gently shake down thermometer, place in sample and wait for reading to stabilize.

What METRIC UNIT would you use: 1) Distance between school and your house 2) Mass of a business card 3) Temperature of this room 4) Width of the paper 5) Volume of a cup of coffee

Reading your measurements Ex. a ruler calibrated to the nearest tenth of a centimeter can be read to the hundredths place by estimating how far between the lines the measurement falls.

Reading your measurements

Reading your measurements This ruler is different from the first one.

Easy enough? This must be done EVERY TIME you make a measurement, for the rest of your life!

Practice as a class

Balance: Calibrated: 0.01 g precision: g Graduated Cylinder Calibrated: 1 mL precision: 0.1 mL ThermometerCalibrated: 1 o C precision: 0.1 o C Ruler: Calibrated: 0.1 cm precision: 0.01 cm

Measurement Lab Objective: use lab equipment to accurately make measurements Do you have appropriate footwear!! Get into your groups. One person gets the goggles Read through and decide who is doing which measure: write name next to procedure

Measurement Lab Groups have been assigned… we are going to walk through the first set of measures. Do NOT go ahead to the second measures!

Practice with a partner Now complete the second try on your lab… Remember: Calibration = value between each mark Precision = the place to which you estimate 10.5 minutes Make sure that you call me over to check and stamp Clean Up!!!

Analysis Complete questions 3 and 4. You did not learn how to do #1 and 2 yet. If you’re done, begin your reading assignment.