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18. It’s interesting to learn some non-metric units of weights and measures. Weights and measures

There are 12 inches in a foot. One inch is 2.5 centimeters. A meter is 39.37 inches.

There are three feet in a yard. There are 5.280 feet in a mile. One mile is 1.6 kilometers.

An average man is about 5 feet, 9 inches tall (5'9"). His average weight is about 150 pounds (lbs). One pound is 450 grams or roughly half a kilogram.

There are 16 ounces in a pound. An ounce is about 28 grams. There are 16 ounces in a pint. A quart is about two pints. There are 2,000 pounds in a ton.

Some Simple Conversions

A. Length

1 kilometer = .62 mile 1 mile = 1.6 km

1 meter = 39.37 inches 1 foot = 3 meter (30 cm)

1 centimeter = .39 inch 1 inch = 2.54 cm

B. Capacity

1 liter = about 1 quart 1 ounce = 28 grams

С. Weight

1 kilogram = 2.2 pounds 1 pound = 450 grams

1 gram = 0.35 ounce

D. Temperature Centigrade Fahrenheit

+100°

+212°

+32°

–18°

Water boils at 212°(Fah.) 100°(C).

Water freezes at 32°(Fah.) 0°(C).

19. Read correctly. Mind all signs and figures. Occurrence of Oxygen

Oxygen is the most abundant element in the earth's crust. It constitutes by weight 89% of water, 23% of air (20% by volume), and nearly 50% of the common minerals (silicates).

The nine common elements that compose the solid crust of the earth are the following:

Oxygen - 46.5%

Iron - 5%

Potassium - 2.5%

Silicon - 28%

Sodium - 3%

Magnesium - 2.2%

Aluminium - 8%

Calcium – 3.5%

Titanium - 0.5%

Oxygen is a colorless, odorless gas, which is soluble in wa­ter - one liter of water at 18°C dissolves 35mL (1mL = l milliliter = 1/1000 liter) of oxygen at 1 atm pressure. Oxygen can become a liquid. Its boiling point is –183°C. It can become a solid. Its freezing point is –218,4°C.

20. Translate the text in written form, mind Modals:

The chemical industry needs instruments for accurate measuring. Good measuring instruments are able to give rap­id results. Without modern instrumentation chemical processes were often controlled by a human operator who had to decide what needed to be done. It was rather difficult to do. The results had often to be checked thoroughly.

There are many different kinds of measuring instruments and there is much information about the instruments which are to be used in chemical plants. The purpose of all measuring devices is to control a chemical reaction. In a process controlled by a human operator, the temperature, for example, can be read from a thermometer. The operator is to decide whether the temperature is all right. Then he has to make some measurements. In the automated system, some mechanical or electrical device must replace the human operator to decide whether a process correction is needed and, if so, the extent of the necessary cor­rection.

UNIT IV The Study of Chemistry and Its Branches

Grammar: Past Simple Tense

Text: Chemistry

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