iGCSE Chemistry Unit 1 - Revision Quiz

Which information is correct about an atom?

• The mass number is the sum of electrons and neutrons

• The mass number is less than the atomic number

• The atomic number changes for different isotopes of an element

• The atomic number is the same as the electron number in a neutral atom

What is the correct electronic configuration for sulfur (16 electrons)?

• 2.10.4

• 2.8.4.2

• 2.8.6

• 2.2.8.4

How is an Rf value in chromatography calculated?

• Spot size / solvent front movement

• Spot movement / solvent front movement

• Solvent front movement / spot movement

• Spot movement / spot size

Why do elements in Group 1 react in a similar way?

• All gain 7 electrons in outer shell

• All have 1 electron in outer shell

• All form ions with a charge of -1

• All form a single covalent bond

What sort of elements normally form covalent bonds?

• Metals with metals

• Metals with non-metals

• Non-metals with non-metals

• Non-metals with noble gases

Why do simple molecular substances have low melting points?

• Weak covalent bonds

• Weak forces between the nucleus and the outer electrons

• Weak forces between the molecules

• Weak forces within the molecules

Why can molten sodium chloride conduct electricity?

• Electrons are free to move

• Ions are free to move

• Positive ions free to attract electrons

• Negative ions free to attract electrons

Which equation is correctly balanced?

• H2 + O2 --> H2O

• SO2 + O2 --> SO3

• N2 + 3H2 --> 2NH3

• Cu + O2 --> CuO2

What is an 'empirical formula'?

• Number of atoms of each element in a molecule

• Total number of atoms in a molecule

• Simplest ratio of atoms of each element in a molecule

• Total simplest ratio of atoms

Which particle has a positive charge?

• electron

• orbital

• proton

• neutron