WELCOM BACK TO CHEMISTRY

20!!!Ms Wiebe

TO DO Start with Attendance/ filling out forms Read Nutana Intro Day 2 Tread through lab safety Take some notes Complete Lab 1 Maybe start measurments section

CHEM 20 DAY 2Starting Unit 1 Pg 7

LAB SAFETY REMEMBER: Marks will be deducted for not following proper safety procedures during the lab, so make sure you understand each rule!

LAB SAFETY1. Safety goggles must be worn at all

times during a lab. This rule must be followed not matter what you are doing during the lab period.

2. Contact lenses are not allowed. Even when worn under safety goggles, since fumes from the chemicals can get under them and cause serious injuries or blindness. If this is a problem, please contact me ahead of time.

LAB SAFETY3. Closed toe shoes and long pants must

be worn in the lab. Sandals and shorts are not allowed.

4. Long hair must be tied back when using open flames.

5. Eating and drinking are strictly prohibited in the classroom, since it is a chemistry classroom and there may be traces of toxic chemicals in the classroom.

LAB SAFETY6. No unauthorized experiments are to be

performed. If you are curious about trying a procedure not covered in the experimental procedure, consult with your instructor.

7. Never taste anything. Chemistry is not a subject where you are allowed to lick the spoon.

8. Never directly smell any gas. Any smelling of gas that is required must by done by means of wafting.

LAB SAFETY9. Coats, backpacks, etc. should be left at

your locker or desk, never on the lab benches or within the area of the experiment.

10. Always wash your hands before leaving lab (with soap).

11. Learn where the safety and first-aid equipment is located.

12. Notify the instructor immediately in case of an accident.

13. Consider all chemicals to be hazardous.

LAB SAFETY14. Know what chemicals you are using. Be

sure to carefully read the label twice before taking anything from a bottle.

15. Excess reagents are never to be returned to stock bottles, as this will contaminate the stock bottles. If you take too much, dispose of the excess. (The proper technique is to put less than required in your flask or weigh boat and slowly add more, until you reach the desired amount)

16. Many common reagents, for example, alcohols and acetone, are highly flammable. Do not use them anywhere near open flames.

LAB SAFETY17. Always pour acids into water. If you

pour water into acid, the heat of reaction may cause the water to explode into steam, sometimes violently, and the acid will splatter.

18. If chemicals come into contact with your skin or eyes, flush immediately with abundant amounts of water and consult with your instructor.

19. Never point a test tube or any vessel that you are heating at yourself or your neighbour.

LAB SAFETY20. Dispose of chemicals properly. Always

consult your instructor before pouring any chemicals down the sink.

21. Clean up all broken glassware immediately and dispose of the broken glass properly.

22. Never leave burners unattended. Turn them off whenever you leave your workstation. Be sure that the gas is shut off at the bench rack when you leave the lab.

23. Beware of hot glass--it looks exactly like cold glass.

LAB SAFETY

LAB SAFETY

LAB SAFETY

LAB SAFETY

BACKGROUND INFORMATION FOR CHEMISTRY LABS

Qualitative vs. quantitative:

Qualitative is using senses to observe and quantitative is using measurement to observe. The first lab we will do is a qualitative lab because we just use our senses to observe instead of taking measurements.

BACKGROUND INFORMATION FOR CHEMISTRY LABSExamples (this is not in your notes)

State whether the following observations are qualitative or quantitative:

1. The substance is red in colour:2. The substance wieghs 3.28 g:3. The substance is 57.3oC:4. The substance is warm:

BACKGROUND INFORMATION FOR CHEMISTRY LABSPhysical Change vs. Chemical Change:

Physical change: Change of state or appearance without changing the actual makeup of the substance.ex: Phase Change: Liquid-solid-gas

BACKGROUND INFORMATION FOR CHEMISTRY LABS Chemical change: Change in the chemical makeup of a substance. Not easily reversed.

signs that a chemical change has occurred:

*_________change, *_________ produced, *_________ produced, *change in _________, *_________ produced, *_________ change, density change (often shown by a

change in volume), change in melting point or boiling point, change in electrical conductivity, change in taste (DON'T EVER TEST)

*easiest (and safest) to observe

WARNING: Sometimes it is easy to get confused

about whether something is a physical change or a chemical change. What you need to think about when you are trying to decide is whether a new substance has been created.

Examples: Burning paper: Melting Ice: Dissolving salt in water:

PROPERTIES OF MATTER:Physical Properties We can observe physical properties

without the chemical identity of the substance being changed (observed with senses).

Examples of Physical Properties that could be observed: What colour is it? How does it smell? What is it’s density? What is it’s melting point? What is it’s boiling point?

PROPERTIES OF MATTER:Chemical Properties Chemical properties can only be

observed when a chemical change takes place.

Examples of Chemical Properties that could be observed: Is it flammable? Does it react with acid?

LAB ONE: PHYSICAL VS CHEMICAL CHANGE Remember you lab safety rules Remember to wear your safety glasses

until everyone is finished the lab and all of the chemicals are cleaned up and put away.

Be sure to make detailed observations. Include observations of substances before,

during, and after the experiments using as much detail as possible. Remember not to make comparisons.

INTRODUCTION: A good understanding of material things

requires and understanding of the physical and chemical characteristics of matter. Such characteristics are familiar to you, and physical and chemical changes are part of your everyday experience. However, you may not yet have a clear idea of the difference between a physical change and a chemical change. You may not yet know exactly how a chemical change is distinguished from a physical change. The purpose of this experiment is to clarify these important distinctions.

The physical properties of a substance are those properties that can be observed and measured without changing the composition of the substance. Because they depend on there being no change in composition, physical properties can be used to describe and identify substances.

The chemical properties of a substance are those properties that can only be observed when the substance is undergoing a change in composition.

INTRODUCTION:

INTRODUCTION: In a physical change, only physical state of a

sample of matter is altered. In chemical changes, new substances, of different chemical composition are produced. A process in which a chemical change takes place is called a chemical reaction. The observable signs that a chemical change has occurred are as follows:

Colour change Gas produced Solid produced Energy Change

Change in heat Light produced

Odor change

PURPOSE: Students will observe properties of several substances and decide whether changes in matter are physical or chemical.

PROCEDURE: Your lab group will rotate through the stations.

You may not be starting with Investigation A, so be sure to check which investigation you are at.

Read through the procedure carefully before you begin

Make your hypothesis before you begin! Make your detailed observations and then

clean up your station. You may empty the test tubes in the sink in the janitors closet. Be sure to wash the test tubes with water and dry them so they are ready for the next group.

Wait for the group in front of you to be done and then move to the next station.

AFTER THE LAB:

Title: (1) You will only need one title for the

entire lab. Objective: (1)

You will only need one purpose for the entire lab

Hypothesis: (7) You will have 7 separate hypothesis.

On for each experiment Procedure/ Materials: (1)

You will have one procedure/materials reference for the Lab

Data: (7) You will have 7 separate sets of

data, describing your observations for each experiment.

Analysis: (7/1) explain observations for all 7

experiments (Ex. In investigation X we observed a colour change from 2 clear transparent solutions to one cloudy orange solution. This means

that a chemical change took place because there was a colour change and colour change is an indicator of a chemical change. In addition to the colour change we observed a solid being produced, since the substance turned from a transparent solution to a cloudy solution. Precipitation is another indicator of a chemical change.

answer the set of questions in the lab

Conclusions: (7) For each experiment give a breif

summary (Ex. Investigation X was a chemical change, my hypothesis was correct)

Sources of error: (1) You will only need 3 sources of error

for the entire lab.

You can work on your lab report. Since this lab report has 7 mini experiments the format will be slightly different from future lab reports