This tiny particle has a positive charge and is found in the nucleus.
Proton
The first electron shell can hold this many electrons.
2
Elements are arranged in order of increasing ______ number.
Atomic Number.
A neutral atom with 12 protons has this many electrons.
12
An atom that gains or loses electrons becomes one of these.
Ion.
This particle has no charge and is found in the nucleus.
Neutron.
The electronic configuration of oxygen.
2,6
Vertical columns on the periodic table are called these.
Groups.
An atom with atomic number 11 has this many protons.
11
An atom that loses electrons becomes a ______ ion.
Cation (positive ion).
The centre of the atom where protons and neutrons are found.
Nucleus.
The electronic configuration of magnesium.
2,8,2
Name the first 20 element with the symbol Si.
Silicon.
Carbon-12 has 6 protons. It has this many neutrons.
6
A sodium atom loses one electron. What charge does it have?
+1
The centre of the atom where protons and neutrons are found.
Nucleus.
This element has the electronic configuration 2,8,7.
Chlorine.
Elements in the same group have the same number of these.
Valence (outer shell) electrons.
An atom has a mass number of 23 and an atomic number of 11. Calculate the number of neutrons.
12
Magnesium loses two electrons. What ion does it form?
Mg2+
An atom contains 8 protons, 8 neutrons and 8 electrons. Name the element.
Oxygen.
This element has 3 electron shells and 1 valence electron.
Sodium.
Group 18 contains these very unreactive elements.
Noble gases.
Explain why Group 1 metals become more reactive down the group.
The outer electron is further from the nucleus and easier to lose.
An atom has 17 protons and 18 electrons. What is its overall charge?
-1