Each of these statements contains an observation and an explanation. Decide whether the statement is correct by deciding whether the observation is correct, and whether it has been explained correctly.
Atomic radii increase going across a period because as more electrons are added to the valence shell, they repel each other and mover further apart.
Atomic radii decrease going across a period becaus as more protons are added to the nucleus the nuclear charge increases, attracting the valence electrons more strongly which pulls them closer to the nucleus.
Atomic radii decrease going across a period because the ionisation energy increases, making it harder for electrons to escape the nucleus.
Atomic radii increase going down a group because there are more filled shells of electrons.
Atomic radii decrease going down a group because as protons are added to the nucleus the nuclear charge increases, attracting all the electrons more strongly.
Atomic radii increase going down the group because the relative atomic mass increases going down the group.
Negative ions are smaller than the atoms from which they were formed because they have lost electrons.
Negative ions are larger than the atoms from which they were formed because the extra electrons in the valence shell repel each other more.
Negative ions are larger than the atoms from which they were formed because the greater number of valence electrons creates more shielding of the nuclear charge.
Positive ions are larger than the atom from which they were formed because the extra valence electrons repel each other more.
Positive ions are smaller than the atoms from which they were formed because they have lost their valence shell of electrons..
Positive ions are smaller than the atom from which they were formed because in losing electrons they have lost mass.
Ionisation energy tends to increase moving across a period because as the number of protons in the nucleus increases, the electrostatic force on each valence electron increases, making it more difficult to remove.
Ionisation energy tends to decrease moving across a period because as the number of electrons in the valence shell increases, they repel each other more and are easier to remove.
Ionisation energy tends to increase going across a period because elements on the right of the periodic table tend to gain electrons not lose them.
Ionisation energy decreases going down a group because as the atoms get larger the valence electrons are located further from the nucleus and thus require less energy added to remove them completely.
Ionisation energy increases going down a group because larger atoms require more energy to remove their electrons.
Ionisation energy decreases going down a group because atoms are more reactive going down a group.