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Факультеттің ОӘК төрағасы________________/А.А.Раманова/

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М.Өтемісов атындағы Батыс Қазақстан мемлекеттік университеті

Факультет: Филологиялық

Кафедра: Шетел тілдері

Шифр, мамандық: 5В060600 «Химия»

Пәні: Жаратылыстану ғылыми мәтіндерінің лингвистикасы

Card № 5

Gas Laws

Boyle’s law. The relation between the volume occupied by a given mass of gas and the pressure to which it is subjected is specified by Boyle’s law. At constant temperature, the volume of a given mass of gas is inversely proportional to the pressure. In symbols, if v is the volume of a given mass of gas and p its pressure, pv = constant. This means that if the pressure is increased, the volume is decreased; if the volume is doubled, the pressure is halved.

Boyle’s law is not accurately true for any gas, but it is approximately true for all.

Gas-Lussac’s law.In 1805 Gay-Lussac and Humboldt carried out a series of experiments to find the volume percentage of oxygen in air. But during this investigation they made a far more important discovery. They discovered the law of gaseous volumes.

The method of finding the volume of oxygen was to mix measured volumes of air and hydrogen and, after exploding the mixture, to note the contraction. Contraction was due to a certain number of cubic centimeters of hydrogen (A) combining with a certain number of cubic centimeters of oxygen (B), forming steam, which immediately condensed to water, occupying a negligible volume compared with the volume of gas from which it had been formed. The old contraction is A + B, and the fractional volume of oxygen is .

A and B were then unknown.

A supplementary experiment was then undertaken to find A and B. Mixtures of hydrogen and oxygen in known proportions by volume were exploded and the gas left over was found. The mean of 24 trials, in one-half of which hydrogen was in excess and in the other half oxygen, was, after making all correction, that 100 parts of oxygen required 199,89 parts of hydrogen. Thus A = 2 B and the volume of oxygen is one-third of the total contraction.

The relation was much simpler than expected, but it might have been a coincidence. Gay-Lussac therefore went on later to investigate other cases of combination of gases. He found that: 100 volumes of hydrogen chloride combined exactly with 100 volumes of ammonia; 100 volumes of sulphur dioxide combined with 50 volumes of oxygen; 100 volumes of carbon monoxide combined with 50 volumes of oxygen to form 100 volumes of carbon dioxide.

In some cases, Gay-Lussac deduced the volume compositions from the composition by weight and the densities of the gases.

The number of repetitions of the same phenomenon show that this simplicity is not coincidence but most probably a general law. The law is stated as follows:

1. Gases combine in simple proportions by volume.

2. The volume of a compound gas always bears a simple proportion to the volumes of the gases from which it has been formed.

This law is known as the law of gaseous volumes.

Words:

transition elements – переходные элементы

to which it is subjected – которому он подвергается

is specified – формируется

inversely proportional – обратно пропорционален

Кафедра шешімімен бекітілді, құрастырылды:

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Кафедра меңгерушісі___________________/ доцент Кисметова Г.Н./

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