Kslmtn Makmal

OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

PART A INSTRUCTION Answer ALL questions QUESTION 1 a)

State the reading of the micrometer screw gauge below.

Solution: Main scale reading

=

0.7 mm

Thimble scale reading =

0.38 mm 1

OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

Diameter

b)

=

1.08 mm

State the reading of the vernier caliper below.

Solution: Reading from the main scale

= 3.1 cm

Reading from the vernier scale

= 0.09 cm

Diameter of the object

= 3.19 cm

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OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

QUESTION 2 Elaborate the following sterilization methods briefly: a) Pasteurization Pasteurization is a method used to prevent or to kill the unwanted bacteria from growing. The pasteurization method uses dry heat. A dry heat at 180°C is passed on the subjects for an hour. The heat is capable to kill all spores.

b) Autoclaving Autoclaving is a sterilization method used to prevent and to kill the unwanted bacteria from growing. It is one of sterilization that used heat. Autoclave sterilization uses under-pressure steam at a high temperature for 20 minutes.

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OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

QUESTION 3 Describe: a)

terrarium A terrarium is similar as a dry habitat, for instant desert or savannah. It is a container and also be formed to create a temperate woodland habitat. This can be created with pebbles, leaf litter and soil. By misting the terrarium, a natural water cycle occurs within the environment by condensation forming on the lid causing precipitation. Plants suitable for this type of terrarium environment include mosses, ferns, yams and tree seedlings.

b)

vivarium A vivarium is a place, specially an indoor enclosure or specifically built container for a suitable habitat that is normally used to study some characteristics in an animal’s life. A vivarium can be used for keeping and raising living animal under natural conditions for observation or research to study organisms such as flies, frogs or worms.

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OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

QUESTION 4 Draw a labeled diagram of a three-pin plug. Label the terminals and the colors of the wires appropriately.

Terminals Live Neutral Earth

Colour codes Brown Blue Yellow and Green Stripes

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OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

QUESTION 5 List FIVE (5) basics materials which must be kept in any first aid box and the function of each material. The First Aid Box should contain those items:ITEMS Absorbent compress

FUNCTIONS A substance that is capable of absorbing. A diverse class of drugs that are applied to skin surfaces or mucous membranes for their anti-

Antiseptics

infective effects. This may be either bacteriocidal (kills bacteria) or bacteriostatic (stops the growth of bacteria). Their uses include cleansing of skin and wound surfaces after injury, preparation of skin surfaces prior to injections or surgical procedures, and routine disinfection of the oral cavity as part of a program of oral hygiene.

Adhesive bandages

Can be used to hold dressings in place, to relieve pain, and generally to make patient comfortable.

Triangular bandages

Use as slings, tourniquets, to tie splints and many other uses.

Medical exam gloves

Which are single use and disposable to prevent cross infection.

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OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

PART B INSTRUCTION: Answer ALL questions. QUESTION 1 You are required to conduct a neutralization experiment with 2.0 L of sulphuric acid with a concentration of 2.0 M and 2.0 M natrium hydroxide. a) State the apparatus used. i.

1 Pipette

ii.

1 Pipette filter

iii.

1 beaker

iv.

1 burette

v.

1 conical flask

vi.

1 retort stand

b) What is the indicator used and state the colour of the indicator. Bromothymol Blue (BTB) c) Write and balance the equation for the above reaction. H2SO4(aq)

+

2NaOH(aq)

NaSO4(aq)

7

+

2H2O(l)

OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

d) Calculate the volume of natrium hydroxide needed. Solution: H2SO4 2L, 2.0 M 2.0 M = n mol H2SO4 2.0 L n = 4 mol H2SO4 1 mole = 2 mole H2SO4 NaOH 4 mole

=

8 mole

8 mole NaOH = 2.0 M y litre y litre

= 4 Litres

Volume of natrium hydroxide is 4 L.

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OPEN UNIVERSITY MALAYSIA SBSC 3303 BASIC TECHNIQUES AND SAFETY IN LABORATORY

QUESTION 2 List FIVE (5) correct techniques handling the chemical spillage with suitable examples. Substance Solid substances at room temperature e.g. zinc powder

Methods of Handling The substance is swept, collected and disposed of in a suitable residue bin. Spillage of acid solution must be washed off with a lot of water and directly channeled to a drainage system. Solid sodium bicarbonate can be used to neutralize the spillage spot. This needs to be washed off as well with a lot of water into the drainage system. Greasy spoilage can be mopped away. The spot can be washed with water and soap if deemed necessary. Dry the spot using a clean cloth. Depending on the amount of spillage, it can either be cleaned with a cloth or a mop. Wash the mop rigorously after using it on a vaporous solvent. When you encounter mercury spillage, the first thing to do is to ensure good air ventilation in the laboratory. If the mercury spillage is small, you can use zinc and sulphur to cover the spot and clean it. A vacuum cleaner or a mercury collector can be used to clear up mercury spillage.

Acid e.g. sulphuric acid

Greasy substances

Vaporous solvent

Mercury

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