SCIENCE TEST ;DD

elements ung main topic for todays vidyeow :0

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LAS 4 : Laboratory rules


1. **%%Keep silent - observe silence inside the laboratory room.%%**

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**%%2. Follow your teacher’s directions - give your full attention while listening to the teacher. Do not begin the experiment until you know what to do.%%**

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**%%3. Notify your teacher of problems - if you spill anything, break a piece of glassware, cut yourself or encounter any problems, notify your teacher immediately.%%**

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**%%4. Know how to use safety equipment in the laboratory - your laboratory may have emergency exits, first aid kits, and eyewash stations. Learn where this equipment is located and how to use it.%%**

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**%%5. Do not hang around - avoid loitering inside the laboratory room.%%**

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**%%6. If it’s hot, let it cool - the tongs, gloves or other equipment may be provided for handling objects, but the safest strategy is to let the objects cool before attempting to move them.%%**

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**%%7. Carry chemicals defensively - when carrying chemicals from one place to another, walk slowly and keep a watchful eye for classmates who may blunder into your path.%%**

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**%%8. Dispose of chemical waste properly - your teacher will tell you how to dispose of chemical waste properly.%%**

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**%%9. No "horseplay" – avoid unnecessary movements inside the laboratory room.%%**

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**%%10. Clean up afterward - leave the laboratory neatly than you found it. Wash your hands before leaving.%%**

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LAS 5 : Elements of the Periodic Table

Examples :

**Non-metals :**

==H - hydrogen –O - oxygen – C - carbon N - nitrogen==

**Metals :**

^^iron - Fe (ferum) sodium^^ – ^^Na (natrium) gold – Au (aurum) silver – Ag (argentum^^)

**Metalloids :**

%%Silicon ( Si ), Boron ( B ), Germanium ( Ge ), Arsenic ( As ) Antimony ( Sb ),%%

%%Tellurium ( Te )%%

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LAS 3 :

Used to hold hot objects :

**Crubicle Tongs**

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A wide – mouthed container used to transport, heat or store substances; not reliable for accurate volume measurement :

**Beaker**

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A small glass container is used to view chemical reactions or to heat small amounts of a substance :

**Test Tube**

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A device to measure the mass of an object or substance. :

**Triple Beam Balance**

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Used to dispense a very small amount of a liquid :

**Dropper**

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Attaches to lab stand and used to hold a variety of lab equipment :

**Ring Clamp**

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Used to hold a variety of lab equipment, especially during a reaction in which a heat source is being used. :

**Ring Stand / Lab Stand**

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Used to measure volume very precisely :

**Graduated Cylinder**

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Used to pour liquids into containers with small openings or to hold filter paper :

**Funnel**

read las 3 im tired of copy and pasting

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