SECOND CLASS L2

What is Science?
1. What do the following words mean? Match them with their definitions
Science, a science, scientific, scientist
– the study of the nature and behaviour of natural things and the knowledge obtained about them
– a particular area of scientific knowledge and study, or the study of an area of a human behaviour
– describes things that relate to science
– someone who works in science
2. What is the difference between ‘science’ and ‘a science’?
3- Define sciences below
I. Mathematics and logic
- not based on experimental testing but they can be considered a part of science because they are
essential tools in almost all scientific study.
II. Physical science
- examines the nature of the universe
III. Life science
- also called biological sciences or biology, the study of living organisms
IV. Social sciences
- deal with the individuals, groups and institutions that make up human society.
7. How do we call the scientists who specialise in the following fields of study? (How are the
names formed).
Ecology……………………, anthropology………………….., chemistry………………….., meteorology
Biology…………………….., sociology…………………., physics…………………, economy…………………





1. Combine the words in brackets with suitable SUFFIXES to complete the sentences.
Choose from the following suffixes:
-er, -or, -ing, -ion, -ness, -ity
1. A _____Boiler___________ (boil) is a closed vessel in which water or other fluid is heated.
2. In chemistry, the ____________________(dense) of many substances is compared to
the______________ (dense) of water.
3. _______________________(transmit) is the act of passing something on.
4. _________________ (hard) is the characteristic of a solid material expressing its resistance to
permanent deformation.
2. Match the following PREFIXES with their meanings.
bi-, mono-, dis-, un-, de-, ultra-, re-
number: bi, mono,
negativeness: dis, un, de
reverse: re
Exercise: Choose the correct alternative to complete these statements.
1. A substance that dissolves in liquid is
a. dissolute b. dissolvable c. soluble
2. A liquid that dissolves substances is a
a. solvent b. soluent c. solutent
3. A material that is hard but breaks easily is
a. battle b. brittle c. bristle
4. If a material bends easily, it is
a. bendible b. flexible c. flectable
5. A material that does not bend easily is
a. rancid b. rigorous c. rigid
6. A metal that can easily be beaten into new shapes is
a. beatable b. malleable c. mullible
7. A material that catches fire easily is
a. flameable b. flammable c. inflammable

Unit 2
If you look chemistry up in Webster s Dictionary, you ll see: "chem·is·try.
1. the science that systematically studies the composition, properties, and activity of organic and inorganic substances and various elementary forms of matter.
2. Chemical properties, reactions, phenomena, etc.: the chemistry of carbon.
My definition is the short and sweet, "scientific study of matter, its properties, and interactions with other matter and with energy". An important point to remember is that chemistry is a science, which means its procedures are systematic and reproducible and its hypotheses are tested using the scientific method. Chemists, scientists who study chemistry, examine the properties and composition of matter and the interactions between substances. Chemistry is closely related to physics and to biology. As is true for other sciences, mathematics is an essential tool for the study of chemistry.
Q: How many meanings of the word chemistry are mentioned in the article?

Q: Which branches of science are, according to the article, closely related to chemistry? Do you agree?
Q: Why, according to the article, is chemistry a science? What criteria are mentioned?
Q: Do you think that mathematics is an essential tool for the study of chemistry, as the article says? Do you as the students of chemistry need to study mathematics?
Q: Find the examples of plural words in the text.
singular ending plural ending
synthesis syntheses
hypothesis ____________
phenomenon phenomena
criterion ____________
Some of these words have double plural form: formula formulae
formulas
Some words follow the English rules: dogma dogmas


Q: Read the text and fill in the gaps with the following expressions in appropriate forms. Use each expression only once.
(chemical formula, chemical equation, proton, neutron, element, electron, atomic nucleus, molecule, cation, anion, chemical compound, chemical reaction, chemical bonds, ion, molecule, atomic number)
An atom is a collection of matter consisting of a positively charged core ( the _ atomic nucleus ) which contains proton and neutron and which maintains a number of

electrons to balance the positive charge in the nucleus. The atom is also the smallest portion into which an element can be divided and still retain its properties, made up of a dense, positively charged nucleus surrounded by a system of electron.
The most basic chemical substances are the chemical elements. They are building blocks of all other substances. An element is a class of atoms which have the same number of protons in the nucleus. This number is known as the atomic number of the element. For example, all atoms with 6 protons in their nuclei are atoms of the chemical element carbon, and all atoms with 92 protons in their nuclei are atoms of the element uranium. Each chemical element is made up of only one kind of atom. The atoms of one element differ from those of all other elements. Chemists use letters of the alphabet as symbols for the elements. In total, 117 elements have been observed as of 2007, of which 94 occur naturally on Earth. Others have been produced artificially.
An Ion is an atom or a molecule that has lost or gained one or more electrons.
Positively charged cation (e.g. sodium cation Na+) and negatively charged anion(e.g. chloride Cl?) can form neutral salts (e.g. sodium chloride NaCl).
Electrical forces at the atomic level create chemical bonds that join two or more atoms together, forming molecule. Some molecules consist of atoms of a single element.
Oxygen molecules, for example, are made up of two oxygen atoms. Chemists represent the oxygen molecule O2. The 2 indicates the number of atoms in the molecule.