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Check the label on all chemical bottles twice before removing any of the contents. Take only as much chemical as you need.

Never work alone in the laboratory. No student may work in the science classroom without the presence of the instructor.

Perform only those experiments authorized by your teacher. Carefully follow all instructions, both written and oral. Unauthorized experiments are not allowed.

4. Do not eat food, drink beverages, or chew gum in the laboratory. Do not use laboratory glassware as containers for food or beverages.

5. Be prepared for your work in the laboratory. Read all procedures thoroughly before entering the laboratory. Never fool around in the laboratory.

6. Always work in a well-ventilated area.

7. Observe good housekeeping practices. Work areas should be kept clean and tidy at all times.

Proceed with caution at all times in the laboratory. Notify the teacher immediately of any unsafe conditions you observe.

Dispose of all chemical waste properly. Never mix chemicals in sink drains. Sinks are to be used only for water. Check with your teacher for disposal of chemicals and solutions.

Labels and equipment instructions must be read carefully before use. Set up and use the equipment as directed by your teacher.

Keep hands away from face, eyes, mouth, and body while using chemicals or lab equipment. Wash your hands with soap and water after performing all experiments

Experiments must be personally monitored at all times. Do not distract other students or interfere with the laboratory experiments of others.

13. Know the locations and operating procedures of all safety equipment including: first aid kit(s) and fire extinguisher. Know where the fire alarm and the exits are located.

Know what to do if there is a fire drill during a laboratory period; containers must be closed, and any electrical equipment turned off.

15. Any time chemicals, heat, or glassware are used, students will wear safety goggles. NO EXCEPTIONS TO THIS RULE!

Contact lenses may be not be worn in the laboratory.

Dress properly during a laboratory activity. Long hair, dangling jewellery, and loose or baggy clothing are a hazard in the laboratory. Long hair must be tied back, and dangling jewellery must be secured. Shoes must completely cover the foot. No sandals allowed on lab days.

A lab coat or smock should be worn during laboratory experiments.

Report any accident (spill, breakage, etc.) or injury (cut, burn, etc.) to the teacher immediately, no matter how trivial it seems. Do not panic.

If you or your lab partner is hurt, inform the teacher immediately. Do not panic.

If a chemical splashes in your eyes or on your skin, immediately flush with running water for at least 20 minutes.

22. All chemicals in the laboratory are to be considered dangerous. Avoid handling chemicals with fingers. Always use tweezers. When making an observation, keep at least 1 foot away from the specimen. Do not taste, or smell any chemicals. If you need to identify a smell, cup your hand and waft.



Check the label on all chemical bottles twice before removing any of the contents. Take only as much chemical as you need.

24. Never return unused chemicals to their original container.

25. Never remove chemicals or other materials from the laboratory area.

 

Relationship (Souvislost) Linking words (spojovací výraz) or expressions (výraz)
Addition (přídavek, dodatek) And, in addition (navíc), moreover (kromě toho), also (také), as well (take, používá se nakonci věty), accordingly (proto, následně)
Contrast Despite (Přestože), in spite of (navzdory), in contrast (v konstrastu), while (zatícmo), nevertheless (nicméně, přesto), on the one hand?. On the other hand (na jednu stranu? na druhou stranu), not only?. But also (ne jenom? ale take)
Reason (důvod) As (jelikož, stejné jako because of ale více formální), due to(kvůli, díky), because of (kvůli vzhledem), because (protože)
Purpose (účel, smysl) In order to (aby), so as to (aby, za účelem), with the aim of
Results (výsledek) So (tak), as a result (následkem), therefore (proto, tudíž), thus (tudíž, vždy na začátku, více formální)
Condition (podmínka) Unless (pokus, jestli ne), otherwise (jinak), as long as (dokud, pokud, jestliže), once (jednou), if (kdyby)
Similarity (podobnosti) Similarly (podobně, rovněž), likewise (podobně, taktéž), accordingly (podle toho, přiměřeně)
Summary (výtah) On the whole (celkem vzato), on balance (po zvážení), in conclusion (závěrem), whereas = while (zatímco)
Other Unfortunately (bohužel, naneštěstí), likely (pravděpodobně)

 

Filtration

- Filtration is a commonly the mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases) by interposing (vložení) a medium through which only the fluid can pass. The fluid that passes through is a called filtrate.

- Laboratory equipment: stirring rod, stand, beaker with filtrated solution, filter from filter paper, funnel, beaker for filtrate, ring clamp

Oxygen

- Oxygen is a chemical element with symbol O and atomic number 8. It is a member of chalcogen group (16 group) on the periodic table and is a highly reactive non-metallic element and oxidizing agent. Oxygen is the third-most abundant element in the universe, after hydrogen and helium. Oxygen has six valence electrons. Oxygen is important part of atmosphere, and is necessary to sustain (udržet) most terrestrial (pozemského) life. Animal and plants need oxygen for respiration. Naturally occurring oxygen is composed (je tvořen) of three stable isotopes 16O, 17O, 18O.

The graduated cylinder The flask is used e. g. The Erlenmeyer flask

is used to measure to hold liquids during heating. is used as a mixing vessel

the volume of liquids in ml. or container

The shield is used to The goggle are used to This vessel is used for The watch glass can be

protect your face to protect your eyes. mixing or holding used as a beaker cover

from broken glass, chemicals. or for heating or

chemicals and flames. evaporation chemicals.

 

The funnel is used Containers are used Beakers are used for The test tube is used to

to remove undissolved for storing chemicals. mixing or holding hold chemicals during

solids from a liquid chemicals. They give heating or other

mixture or to help only approximate reactions.

pour a liquid into a measurements of

container. volume.

 

Pipets are used to measure The thermometer measures The stirring rod is used the filtering flask

liquids. Volumetric pipets temperature. to stir chemicals. can speed up

are used to measure one filtration.

amount only. Graduated

pipets measure many

different amounts.

 

The evaporating dish The spot plate is used for The crucible is used during

is used to evaporate a observing reactions that heating at high temperatures.

liquid from some chemicals. occur in the wells. Next to it is a spatula.

 

Forceps are used to pick up The test tube stand The burner is used for The wash bottle is

small items. supports the test tubes. heating. used to rinse glassware.

 

The test tube clamp holds The ring clamp is used to hold Crucible tongs are used to pick

a test tube during heating. e. g. a funnel during filtering. up and hold a crucible.

The clay triangle is used to The wire gauze can support a Gloves are used to protect

support or hold a crucible during beaker or a flask during our hands.

heating or funnel during filtering. heating. It spreads the flame

evenly.

 

The ring stand can The mortar is a dish and the pestle

support glassware. is the grinder. They are used to

crush or grind chemicals

 


Date: 2016-06-12; view: 306


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