1.48 understand that an electric current is a flow of electrons or ions

An electric current is the flow of electrons or ions because they have a charge.

1.38 describe the formation of a covalent bond by the sharing of a pair of electrons between two atoms

Covalent bonds

When two non-metallic elements combine together they often share  electrons between them. When an atom of hydrogen, H and an atom of chlorine, Cl, combine to form hydrogen chloride, HCl, the atoms come close enough together for their outer electron (valence) shells to overlap.

Atomic Structure 1.15 deduce the number of outer electrons in a main group element from its position in the Periodic Table.

Number of electrons in groups of the Periodic Table

As you can see, some of the columns of the table have numbers above them, this tells us how many electrons are in the outer shell of that group. It is a good idea to label this on your periodic table in your chemistry exam.

Atomic Structure 1.10 recall the relative mass and relative charge of a proton, neutron and electron

Relative mass and relative charge

Neutron: 

Relative charge: 0

Relative mass: 1

Proton:

Relative charge: +1

Relative mass: 1

Electron: 

Relative charge: -1

Relative mass: 1/1836

Nearly all the mass is concentrated in the nucleus.

Atomic Structure 1.9 understand that atoms consist of a central nucleus, composed of protons and neutrons, surrounded by electrons, orbiting in shells

Protons, neutrons and electrons


As you can see from the diagram, in the centre of the atom is the nucleus, which contains protons (positive charge) and neutrons (no charge). Orbiting the nucleus is a series of shells, which hold electrons (negative charge). The electrons are much smaller than the protons and neutrons. 
The first shell outside the nucleus can hold 2 electrons, the second can hold 8 and the third can hold 8.