1. Fill in the text with a suitable word for each blank space. There are two extra words you do not need to use.
container • elements • gases • mass • particles • pressure • shape • states • structure • substances • temperature • volume
Matter is what all (1) ....................... consist of and (2) ....................... are the chemical building blocks of matter. Elements cannot be broken down or changed into another substance. Matter has four (3) .......................: solid, liquid, gas and plasma. It has the following physical properties: a solid has a fixed volume, which does not vary much with (4) ....................... and a rigid shape. The (5) ....................... of liquids changes depending on the (6) ......................., while changes in temperature and (7) ....................... may modify their volume. Neither liquids nor solids can be compressed. (8) ....................... expand in volume and shape until they fill their container completely, and their (9) ....................... is affected by temperature and pressure. Highly-charged (10) ....................... with extremely high kinetic energy make up plasma, which is not a common state of matter on Earth. There are other known states of matter, such as BEC (Bose-Einstein Condensates), also called ‘the fifth state of matter’.
2. Choose the right option.
1. ....................... are located in the nucleus of an atom.
- a. Protons and electrons
- b. Protons and neutrons
- c. Protons and ions
2. The atom is neutral because the number of ....................... equals the number of .......................
- a. protons - electrons
- b. protons - neutrons
- c. neutrons - electrons
3. The atomic number is the number of ....................... in the nucleus of the atom.
- a. protons
- b. electrons
- c. neutrons
4. An element’s mass number is the sum of ....................... and ....................... in its .......................
- a. electrons - protons - atom
- b. protons - neutrons - nucleus
- c. electrons - neutrons - nucleus
5. A ....................... is the smallest ....................... in a chemical ....................... or compound that has the chemical properties of that element or compound.
- a. particle - element - molecule
- b. element - particle - molecule
- c. molecule - particle - element
3. Answer the following questions.
- What are molecules made up of? ...........................................................
- What are compounds? ...........................................................
- How does an ionic bond form? ...........................................................
- How does a covalent bond form? ...........................................................