In the chemical Laboratory

INTRODUCTORY TEXT

TOPICAL VOCABULARY

reagent – реактив, реагент

potassium – калий

ammonium – аммиак

sodium – натрий

alkali -щелочь

nitric acid – азотная кислота

sulphuric acid – серная кислота

hydrochloric acid – соляная кислота

methylene green – метиленовая зелень

phenolphthalein -фенолфталеин

flask -колба

volumetric flask – мерная колба

measuring glass -мензурка

pipette -пипетка

funnel -воронка

glassware – стеклянная посуда

retort -реторта

graduated cylinder – мерный цилиндр

burette -бюретка

rack – полка (узкая)

running water – проточная вода

distillator – дистилляционный аппарат

analytical balance -весы

burner -горелка

vessel -сосуд

weigh -взвешивать

obtain -получать

amount -количество

The students of the pharmaceutical department usually have practical classes in Chemistry in chemical laboratory. There they carry out various experiments, they work with different substances.

The chemical laboratory consists of several rooms:

· a room for storing the necessary substances,

· a room for recording the obtained findings,

· a room for washing laboratory vessels.

The laboratory vessels and glassware are divided into three groups:

· glassware for general use,

· glassware for special use,

· glassware for measuring.

Glassware for general use	Glassware for special use	Glassware for mea-suring
Test-tubes, Funnels, Flasks of different shapes and sizes, Retorts	Special vessels for the determination of molecular weights, for the determination of melting and boiling points.	Cylinders, Burettes, Graduated flasks, Measuring glasses, Pipettes,

A chemical laboratory is equipped with different apparatuses and instruments: microscopes, analytical balances, distillators, burners.

There is a special room for weighing which is equipped with a set of balances for different use. The windows of the weighing-room should overlook the North as the sun may prevent accurate weighing of the substances.

On the shelves and racks besides empty vessels there are many bottles and boxes with chemical substances called reagents. The most widely used reagents which are available at every laboratory are: acids (nitric, sulphuric, hydrochloric); alkalis (ammonium solution, potassium solution, sodium solution); oxides, inorganic salts, indicators (phenolphthalein, methylene green).

Reagents which are used in large amounts are supplied in big boxes or bottles. Reagents which are seldom used are supplied in amounts up to 10 or 1g or even less.

When students come to work to the laboratory they should put on white gowns and wash their hands with running water before work and after it.

Дата добавления: 2014-11-18