Writing

Task 14. Read the following text and fill in the gaps in the chain of energy releasing process. Then use linking words below to indicate sequence of the process and write the resulting paragraph.

Food is a good example of stored chemical energy. This energy is released during digestion. Molecules in our food are broken down into smaller pieces. As the bonds between these atoms loosen or break, a chemical reaction will occur, and new compounds are created. When the bonds break or loosen, oxidation occurs almost instantly.

In the example above, notice that new compounds are formed from the breakdown of other molecules or atoms. Chemical reaction causes that.

A chemical reaction is involved in this breakdown. The energy produced keeps us warm, maintain and repair bodies, and makes us able to move about. Different foods store different amounts of energy. Energy in food is measured in kilocalories (or calories). Can you think of some very good examples of chemical energy?

Energy releasing process during digestion:

1) molecules in the food are broken down

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2) ______________________________________________________________

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3) ______________________________________________________________

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4) the new compounds are created

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5) oxidation occurs

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6) ______________________________________________________________

Linking words for sequence or order

Firstly …, primarily …, then …, after this …, following this …, next …, when (this is done …), once (this is done …), while (something else is happening …), simultaneously…, at this point…, subsequently…, at this time …, meanwhile …, ultimately …, eventually …, previously …, afterwards …, finally

Unit 4 corrosion phenomenon lead-in

Task 1. Use your general knowledge on the properties of materials to choose 10 phrases related to causes of corrosion.

acidic substances touching metal, greenhouse gas emissions, salty air environment, significant costs, electrochemical change, environmental conditions, presence of moist, deforming force, gradual destruction, global warming, chemically unstable, elastic deformation, temperature considerations, impurities in the metal, oxidation process, change of water from a liquid to a gas, deforming force, kinetic energy of the particles.

Task 2. Read and memorize the following words and phrases for better text comprehension. Then choose the words from the vocabulary list to complete the sentences below.

deterioration	руйнування
to exacerbate	підсилювати
consideration	причина, фактор
exposure	підпадання під вплив
electrochemical cell	електрохімічний елемент
availability	відповідність вимогам
maintainability	надійність експлуатації
dissolved species	розчинені компоненти
proximity	близькість

1. The processes leading to the____ of building stone have been the subject of numerous publications.

2. The____ of the heat source allowed it to be detected by the sensor.

3. We will also highlight a number of practical ____ that have not received as much attention in the available literature.

4. Chemical____ is a measure of how stable a substance is when mixed with another substance.

5.____can be defined as the ease in time and resources of retaining equipment in or restoring it to a specified operational condition.

6. ____ is an important metric used to assess the performance of repairable systems, accounting for both the reliability and maintainability properties of a component or system.

Task 3. Choose the right option to complete the following statements. Then read the text of Task 4 to check your answers.

1. Corrosion can be defined as the gradual degradation of a material due to a reaction with its ……
a) medium	b) environment	c) nature
2. There are many different methods of corrosion …… and control.
a) resistance	b) prevention	c) appearance
3. There is no material resistant to all corrosive situations but materials …… is critical in preventing many types of failures.
a) condition	b) selection	c) composition
4. The corrosion situation is more …… if more than one metal is present within the system.
a) stable	b) complex	c) positive
5. The corrosion process is usually …… in nature, having the essential features of a battery.
a) physical	b) electrochemical	c) chemical
6. Corrosion testing is generally performed to evaluate means for protecting a material from environmental ……
a) attack	b) influence	c) pollution