1. Please read the text and answer the questions that follow it:
A ring stand is probably the handiest single support you can own. It can be used to
hold a funnel or to support a flask, beaker or crucible over a flame.
A tripod may be substituted for a ring stand. This three-legged iron stand may have
a single ring for a top or it may have several concentric rings which can be removed
or added to suit the size of the apparatus to be heated.
If you have a supply of gas in your lab, a Bunsen or a Fisher burner will solve practically all your heat problems. If you have not, you will have to improvise. A small
alcohol lamp will generally do for heating test-tubes. A larger alcohol or gasoline
burner or an electric hot plate will heat flasks and beakers. A propane soldering
torch, provided with a flame spreader, will give you plenty of heat.
The Bunsen burner may be bought in types for either natural or artificial gas. A
wing-top attachment will spread the flame for the working glass. The hottest part of
a Bunsen flame is a point just inside the tip of its outer cone. To light a Bunsen burner, close the air supply at the base of the burner, turn on the gas at the source and
bring a lighted match just above the mouth of the burner from one side. Then gradually open the air supply until the original luminous yellow flame has turned nonluminous and blue.
The Fisher burner is an improved modern form of air-gas burner which costs more
than the Bunsen type but which gives a broader flame and considerably more heat.
a) What are ring stands and tripods used for?
b) What kinds of apparatus are used for heating and what can be done if they are not available?
c) What is the difference between a Bunsen and a Fisher burner?
d) What are test-tubes and beakers used for?
e) What other sorts of glassware can be found in a lab?
2. Translate the following sentences into English (using the gerund).
a) Haben Sie etwas dagegen, das Experiment noch einmal durchzuführen?
b) Er äußert seine Meinung nicht gern
c) Ich schlage vor, ihn zu fragen
d) Dieses Handbuch zu lesen, ist sehr nützlich
e) Nicht auf die Experten zu hören, kann sehr teuer werden.
f) Vermeiden Sie es, die Proben zu überhitzen.
g) Ich bin daran interessiert, die Ergebnisse so schnell wie möglich zu veröffentlichen (publish).
3. Complete the sentences with the expressions in brackets in their correct forms.
4. Below are some definitions from the world of computers. What does each describe?
a) This is a programme which can attach itself to other programmes and reproduce
itself, spreading from one computer to another through a network or on data
storage devices. These programmes are written deliberately by criminals to damage data or just to annoy people. They can make strange things happen to your
data or write messages on your screen.
b) It is a website or service that offers a broad array of resources and services, such
as e-mail, forums, search engines and online shopping malls.
c) Some networked computers (and some stand-alone computers) have a special protection. You have to type in a secret word before you are allowed to see the data. This stops people using the network to find, or access, secret data that is held on other computers
5. You certainly have a computer or have used one. Do you like working with computers? Why? Why not? (Write about 150 words.)
2.00
2.00
;)
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