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 Physical (heat, noise radiation)  Chemical (inhalation or skin contact with chemicals)  Biological (Due to exposure to bacteria, viruses, and parasites and their entrance to the body via injures)  Mechanical (operation of instruments and equipments)  Psychological and social (any unfavourable conditions in the university environment) 2

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Following safety rules protect your health. 14

15 Safety items in the laboratory: Locate and read the instructions on: a. Fire extinguisher b. First aid kit

 Wear your lab coat once you entered the lab  Keep your working area of the bench tidy  Read labels carefully  Strong acids and alkali shouldn’t be washed down the sink  Label all test tubes and flasks clearly and properly  When heating a test tube, point the mouth of the tube away from yourself and from others 16

 Do not eat or drink in the lab  Clear up the working area at the end of each lab  Wash your hands with soap and disinfectant before leaving the lab  Never remove chemicals from the lab 17

 Report all accidents and injuries to your instructor immediately  Long hair must be tied back during lab sessions  Never mix chemicals together  Never return excess reagents to the stock bottle 18

 Rinse with tap water  Scrub with detergent and a brush  Rinse with tap water  Rinse with distilled water  Allow to dry in an inverted position 19

 Do not use chipped or broken glassware  Never carry large bottles by their neck  Do not force stoppers too firmly into bottles  dispose of broken glass using paper towels and gloves 20

Wear a protective goggle when working with corrosive reagents 21

GLOVES 22 Always wear a suitable pair of gloves when handling hazardous materials

Protect yourself when handling UV radiation 23

Hazards signs should be provided in lab and building entrance to act properly at the emergency situations 24

All refrigerators should carry signs such as: “No food” “No volatile substances” Unless it was for keeping foods or explosive substances 25

Clear and informative Labels 26

Enough information to be able to estimate the risk and manage it 27

Emergency tools 28

MANAGING RISKS BY FOLLOWING THE SFETY RULES 29

Mark the places which contain emergency tools clearly 30

Indicate clearly places that contain the first aid and spill kits so you can reach easily at the time of accidents 31

Powder chemicals can be stored alphabetically or in any other comfortable way 32

Liquid chemicals should be stored according to their classifications. 33

Flammable substances > 1 Gallon should be kept in tightly closed special containers, while > 10 Gallons should be kept in a special cupboard 34

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36 Sharp objects and broken glass: Scissors, scalpels and razor blade must be placed in safe position when not used Needles, scalpel and razor blades etc.. Should be disposed in special containers

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 For holding chemicals  Come in various sizes 39

 For holding small amount of chemicals  Receptacle where simple reactions may be carried out especially if it involves heating 40

 Holding liquids  Receptacle where chemical reactions may be carried out 41

 Measure volumes of liquids 42

 Receptacle where chemicals may contained while being heated 43

 Holding liquids  Receptacle where chemical reactions may be carried out to prepare gases 44

 Receptacle where chemical reactions may be carried out  Must be supported by retort stand  Round bottom allows even heating of liquids 45

 Must be supported by retort stand  Used for simple distillation or fractional distillation  Side arm usually connected to a condenser 46

 Transfer liquid to a receptacle with small opening  Support filter paper when carrying out filtration 47

 Comes in various sizes  Used to accurately measure and transfer fixed volumes of liquids  With pipette aid 48

 To transfer known volumes of liquids to another receptacle  Accuracy up to 0.1 cm 3 49

 For transferring small amounts of liquid 50

51 Used for measuring volumes that ranges between ml

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 Used for providing heat during experiments 53

barrel air hole collar gas tubing gas tap 54

LABORATORY EQUIPMENT Beam Balance Used to find the mass of various materials. Electronic Balance Used to find the mass of materials. This particular balance is not as precise as the beam balance.

Hot Plate Used for heating liquids. Gas Jet and Outlet The hose from the Bunsen burner connects to the jet. LABORATORY EQUIPMENT

Ring Stand Used in many lab activities as the support for other apparatus.

LABORATORY EQUIPMENT Typical Setup Ring stand shown with iron ring, wire gauze and a beaker. The Bunsen burner would go below the "stage". Clamp May be attached to a ring stand and be made to hold a test tube or thermometer.

MEASUREMENTS

 Simple to use  A few base units make up all measurements  length - meter  mass - grams  volume - liters  temperature – degrees Celsius  time - seconds

Length - the distance between two points standard unit is meter (m) long distances are measured in km Measured using a meter stick or ruler

 Mass is a measure of the amount of matter in an object. Mass does not depend on location.  Weight is a measure of the gravitational force acting on an object. Weight depends on location.  Chemist measure grams or milligrams

 3 scales  Fahrenheit  Celsius  Kelvin

 Converting Between Temperature Scales  o F = (1.8 x o C) + 32  K = o C

 Mass is the amount of matter that makes up an object.  A golf ball and a ping pong ball are the same size, but the golf ball has a lot more matter in it. So the golf ball will have more mass.  The standard international (SI) unit for mass is the gram.  The mass of an object will not change unless we add or subtract matter from it.

 We will use a triple beam balance scale to measure mass.  Gravity pulls equally on both sides of a balance scale, so you will get the same mass no matter what planet you are on.

 Volume = length x width x height  Units – m 3  Chemist tend to use milliliters (mL) or Liters (L)

 The base unit for volume is the Liter.  We measure volume with a graduated cylinder.

 Liquids form curved, upper surfaces when poured into graduated cylinders  To correctly read the volume, read the bottom of the curve called the meniscus

 Volume - length x width x height  V = 2.8 cm x 3.2 cm x 2.5 cm  V = 22.4 cm3  Measured with a ruler

 When the metric system was created, they decided that 1 cm 3 of water would equal 1 milliliter of water and the 1 mL of water will have a mass of one gram.  1cm 3 water =1 ml of water = 1 gram

 1 cm 3 water = 1 mL of water = 1 gram  So what would be the mass of 50 mL of water be?  50 grams  So what would be the mass of 1 liter of water be?  1 L = 1000 mL so its mass would be 1000 grams or a kilogram.

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