Аврамова Интродуцтион то Нуцлеар Енглиш 2011

smallest that is still salt is called a molecule. All matter consists of molecules. However, all molecules are not alike. A molecule of sugar is different from a molecule of salt.

But this is not the whole story. Molecules are made of even smaller parts, which are called atoms. We know that at least 92 different kinds of atoms occur in nature. These different kinds of atoms are known as elements. Combining atoms of different elements or atoms of the same element makes molecules. The kind of molecule depends on which atoms combine. This process of combining atoms is called a chemical reaction. In chemical reactions, atoms do not change; instead, they combine with other atoms or separate from other atoms.

So, atoms are basic building blocks of everything in the universe. They are the smallest particles of matter that have all of the characteristics of an element. The word «atom» comes from Greek and means «indivisible». However, as small as atoms are, they have a complicated structure and are made of even smaller particles. There are three basic particles in most atoms – protons, neutrons, and electrons.

Protons carry a positive electrical charge. Neutrons have no charge at all. Protons and neutrons together are contained in the nucleus. Electrons have a negative electrical charge and revolve around the nucleus in their orbits or shells. Normally, an atom has the same number of protons and electrons. If the positively charged protons and the negatively charged electrons are equal in number, they balance each other. As a result, in the normal state the atom is electrically neutral.

One should distinguish between the atomic number and the atomic weight. The atomic number is determined by the number of protons or electrons. On the other hand, the atomic weight is determined by the number of protons and neutrons.

Actually, the properties of the atom depend on the number and arrangement of the fundamental particles in the atom.

Exercise 1. Match the two parts of the sentences. Look at Reading 4-A to help you.

1.Although the word «atom» means «indivisible»...

2.The atomic number is determined by ...

3.On the other hand, the atomic weight is determined by...

4.In the normal state, the atom is electrically neutral, ...

5.The properties of the atom depend on ...

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A. ... the number of protons or electrons. B. ... the number of protons and neutrons. C. ... it has a complicated structure.

D. ... the number and arrangement of the fundamental particles in the atom.

E. .. because the number of electrons is equal to the number of protons.

Exercise 2. Use Reading 4-A to find the English equivalents for the following Russian phrases.

Материя, состоять из атомов, содержать частицы, означать (3 формы), неделимый, на самом деле, ядро – ядра, ядерная физика, сложное строение, различать, атомный вес, атомный номер, определять, заряд – заряженный, в обычном состоянии, быть равным по количеству, зависеть от, свойство – свойства, расположение, положительный – отрицательный.

Exercise 3. Test yourself by covering the right-hand column and trying to answer the questions in the left-hand column. Compare your own answers with those given in the right-hand column.

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Reading 4-B

Isotopes

The nucleus in every atom always has the same number of protons. However, the number of neutrons may vary. Atoms that contain the same number of protons, but different numbers of neutrons, are called isotopes of the element.

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All atoms are isotopes. To show which isotope of an element we are talking about, we add the number of protons and neutrons together. Then we write the sum after the chemical symbol for the element. For example, in the nucleus of one isotope of uranium, there are 92 protons and 143 neutrons. We refer to it as uranium-235 or U-235 (92+143=235).

Isotopes of a given element have the same chemical properties, but they may have different nuclear properties. Also, isotopes of an element have different numbers of neutrons and the same number of protons. However, some proton-neutron combinations are more stable than others. Some unstable isotopes stabilize themselves by emitting energy rays. Others may emit particles and change into different elements. These rays and particles are called radiation, and the process in which isotopes emit radiation to become more stable is called radioactive decay.

Exercise 1. Complete the sentences with the words from both texts.

1.The smallest particles of matter that have all the characteristics of an element are...

2.Atoms of an element containing the same number of protons, but

different number of neutrons are called…

3.Positive charge carriers are known as...

4.Negative charge carriers are referred to as…

5.The rays and particles emitted by unstable isotopes are called…

6.The process of isotopes emitting energy rays and particles to be-

come more stable is known as…

Exercise 2. Match the two parts of the sentences. Look at Reading 4-B to help you.

1.Atoms that contain the same number of protons, but different numbers of neutrons, ...

2.To show which isotope of an element we are talking about, ...

3.Isotopes of a given element have the same chemical properties, ...

4.Unstable isotopes stabilize themselves ...

5.The process in which isotopes emit radiation to become more stable ...

A. ...but they may have different nuclear properties. B. ...is called radioactive decay.

C. ...we add the number of protons and neutrons together.

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D. ...are called isotopes of the element.

E. ...by emitting energy rays or particles.

Exercise 3. Use Reading 4-B to find the English equivalents for the following Russian phrases.

Одинаковое количество протонов, одинаковые химические свойства, разные ядерные свойства, отличаться, складывать – сумма, стабильный – нестабильный изотоп, стабилизировать, испускать лучи/частицы/радиацию, радиоактивный распад.

Exercise 4. Read the text about isotopes and answer the questions below.

1.Do atoms have the same number of protons and neutrons?

2.What is meant by isotopes of the element?

3.What is an isotope identified by? Give an example, please.

4.In what way do the isotopes of a given element differ from each other? In what way are they similar?

5.How do unstable isotopes stabilize themselves?

6.What is meant by radioactive decay?

UNIT V

Reading 5-A

Types, Forms and Sources of Energy

Energy equals milk chocolate squared (mc2).

Energy is the ability to do work. Whenever work is done, energy is used. We need energy to power our factories and businesses, to heat and light our homes, to run our appliances and machines, to fuel our cars.

We can divide energy into two basic types: kinetic energy and potential energy. Potential energy is stored energy that is waiting to be used. Kinetic energy is energy in action.

There are many forms of potential and kinetic energy. These include mechanical, chemical, thermal, electrical, radiant, and nuclear.

1.Mechanical energy is the energy of motion.

2.Chemical energy is the energy released when the chemical composition of materials changes.

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3.Thermal energy is heat energy which is often used to generate electricity.

4.Electrical energy is the movement of electrons through a conductor, such as a copper wire.

5.Radiant energy is the energy in light.

6.Nuclear energy is released when certain elements change the make-

up of their nuclei. Sometimes they split apart (nuclear fission) or sometimes two nuclei are forced together (nuclear fusion).

The five main or primary energy sources that we use today are:

1.Fossil fuel energy (coal, natural gas, oil)

2.Geothermal energy ( heat from inside the Earth)

3.Nuclear energy

4.Solar energy and

5.Tidal energy (the effect of the gravity of the Moon on the oceans).

There is a limited amount of fossil fuels on Earth. Consequently, fossil fuels are a nonrenewable energy source. Nuclear fuels, such as uranium and plutonium, are also nonrenewable energy sources. Geothermal, solar and tidal energy are called renewable sources because they cannot be used up.

Energy can change from one form into another, but cannot be created or destroyed. In fact when we use energy, we simply convert it from one form into another.

Most energy conversion processes are not very efficient, as a result, they lose energy to the environment. The inefficient conversion and use of energy costs money and wastes nonrenewable resources. This is why people today are looking for ways to save energy. Energy conservation is not an energy source, we can use it to extend the length of time nonrenewable energy sources will be available in the future.

Exercise 1. Complete the sentences with the words from the text.

1.Ability to do work is...

2.Stored energy that is waiting to be used is known as…

3.Energy in action is…

4.Energy of motion is…

5.The energy released when the chemical composition of materials

changes is called…

6.Heat energy is another name for …

7.The energy in light is known as …

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8.The energy released when certain elements change the make-up of their centers is…

9.Energy sources that cannot be used up are called…

10.Saving energy by carefully using energy resources and trying to

convert energy as efficiently as possible is known as…

Exercise 2. Match the two parts of the sentences. Look at Reading 5-A to help you.

1.Whenever work is done, ...

2.Fossil fuels are a nonrenewable energy source because...

3.Geothermal, solar and tidal energy are called renewable sources...

4.Energy cannot be created or destroyed, ...

5.Most energy conversion processes are not very efficient, ...

A. ...only converted from one form to another.

B. ...energy is used.

C. ...as a result, they lose energy to the environment.

D. ...because they cannot be used up.

E. ...there is a limited amount of fossil fuels on Earth.

Exercise 3. Use Reading 5-A to find the English equivalents for the following Russian phrases.

Способность совершать работу, нуждаться в энергии, разделять на два типа, высвобождать энергию, хранить энергию, двигаться – движение – движение электронов, расщепляться, ядерное деление, ядерный синтез, возобновляемые источники энергии, ископаемое топливо, терять тепловую энергию, преобразовывать энергию – преобразование энергии, энергосбережение, расходовать энергию впустую, искать способы экономить энергию, эффективный/неэффективный, быть в наличии.

Exercise 4. Give the derivatives.

1.To heat – тепло, отопление.

2.To light – свет.

3.To divide – неделимый.

4.To store – запасенный, хранилище.

5.To radiate – радиация, лучистый.

6.To move – движение (2).

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7.To compose – состав.

8.To convert – преобразование.

9.To conserve – сохранение.

10.A source – ресурсы.

11.Chemistry – химический.

12.To conduct – проводник.

13.New – невозобновляемый.

14.Sun – солнечный.

Exercise 5. Read the text again and answer the questions below.

1.What is energy?

2.What are the two basic types of energy?

3.What is meant by potential energy? What is meant by kinetic energy?

4.What forms of energy do potential and kinetic energy include?

5.What is mechanical energy? What is thermal energy? What is radiant energy? Chemical energy?

6.What are the five primary energy sources we use today?

7.Which of them are nonrenewable? Why? Name the renewable sources of energy.

8.Can energy be created or destroyed? What do we mean when we say we use energy?

9.Why are energy conversion processes inefficient?

10.How can energy conservation help people?

Reading 5-B

Power

WATT is the unit of power?

Power is a measure of how fast energy is being transferred or converted – or how fast work is being done. Power is measured in watts (W). The unit is named after James Watt, a Scottish engineer and inventor who made a vital contribution to the practical development of steam engines.

The «power output» of a device tells you how much energy is converted into the required form each second. It is always less than its «power input», that is, the rate at which energy is supplied, because of dissipated energy.

The maximum power output of engines is often expressed in «horsepower» rather than in watts or kilowatts. At one time, the horse-

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power was only a rough unit of measure. Now the value of one horsepower is standardized, with a fixed value of 746 W.

Exercise 1. Match the following terms with their definitions below.

a)power;

b)horsepower;

c)watt;

d)power input;

e)power output.

1.The rate at which energy is supplied.

2.A fixed value of 746 W.

3.The rate at which energy is converted into the required form.

4.A measure of how fast energy is transferred or converted.

5.Unit of power.

Exercise 2. Answer the questions below.

1.What is power?

2.What is the unit of power?

3.Who is James Watt?

4.Why is the power output always less than the power input?

5.What is the horsepower?

6.What is the value of the horsepower in watts?

UNIT VI

Reading 6-A

Renewable Energy Sources

If it weren’t for electricity, we’d be watching television by candlelight.

Besides fossil fuels, the natural world contains other sources of energy, many of them renewable, for example fission and fusion, wind power, solar energy, the power of water. The question is: which of them can provide a clean and cheap alternative to fossil fuels? To put the choices into perspective, let us look briefly at the potential and limitations of some of these sources of power.

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Wind power has been used for hundreds of years in the form of the old-fashioned windmill. The modern aero-generator, which converts wind energy into electrical energy, is relatively cheap and does no damage to the environment, but wind power cannot be used in places where there is not much wind!

Water energy is plentiful. In Norway, which has many suitable mountain rivers, 90 percent of the country’s energy comes from hydroelectricity. Hydro-electric power is clean and can be environmentally friendly. But wave and hydro-electric power stations can upset the local ecosystem. For example, the Aswan Dam in Egypt caused many unforeseen environmental problems. The land in the Nile Valley became dry and unproductive. People whose families had farmed this land for thousands of years had to leave in search of a more fertile place to live.

Solar power is energy generated from the sun. Watches and calculators, as well as satellites in space, use solar batteries. Solar panels on the roofs of houses can heat water directly for bathing and central heating systems. Solar power is potentially one of the most important sources of energy in the world. A major disadvantage of solar energy is that the amount of energy generated depends on the season, the part of the world and the weather on a particular day.

Geothermal energy is energy from the hot center of the earth. It is already widely used to heat homes and swimming pools in New Zealand, and in a few places it is used to generate electricity.

There is no doubt that clean electricity from renewable sources – solar, wind, and geothermal power – deserves strong support. But the collective capacity of these technologies to produce electricity in the decades ahead is limited. The International Atomic Energy Agency projects that these renewables can only provide around 6% of world electricity by 2030.

To date, only hydroelectricity and nuclear power have been significant alternatives to fossil fuel. Of these, nuclear power has a better outlook for the future, because it can generate a lot of clean, safe and cheap electricity with no greenhouse gas emissions.

Exercise 1. Match the two parts of the sentences. Look at Reading 6-A to help you.

1.Besides fossil fuels, the natural world contains many renewable sources of energy, ...

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