Topic 1 - Ionic bonding Flashcards
What is an ionic bond?
A bond between a metal and non-metal involving the transfer of electrons.
In terms of electrons, describe what happens to the metal and non-metal when an ionic bond forms
- The metal atom loses electrons to become a positively charged ion (cation).
- The non-metal gains electrons to become a negatively charged ion (anion).
What is an ion?
An ion is an atom or group of atoms with a positive or negative charge.
If an ion is positively charged, has it lost or gained electrons?
- It has lost electrons.
- There are fewer negatively charged electrons to cancel out the charge of the positive protons.
- This means the overall charge becomes positive.
Na+ has the atomic number 11 and the mass number 23. How many protons, neutrons and electrons are in this ion?
- Protons: 11
- Electrons: 10
- Neutrons: 12
O2- has the atomic number 8 and the mass number 16. How many protons, neutrons and electrons are in this ion?
- Protons: 8
- Electrons: 10
- Neutrons: 8
Why do elements in groups 1, 2, 6 and 7 readily form ions?
So they become more stable and achieve the electron structure of the noble gases (group 8).
What type of ions do elements in group 1 and 2 form?
Cations (positive)
- Group 1 metals will form 1+ ions
- Group 2 metals will form 2+ ions
What type of ions do elements in groups 6 and 7 form?
They are non-metals so form anions (negative)
- Group 6 wil form 2- ions
- Group 7 will form 1- ions
What does it mean if an ionic compound ends in -ide?
The compound contains 2 elements.
What does it mean if an ionic compound ends in -ate?
The compound contains at least three elements, one of which is oxygen.
Describe the structure of an ionic compound
- Lattice structure.
- Regular arrangement of ions.
- Ions held together by strong electrostatic forces between ions with opposite charges.
What is the chemical formula of sodium oxide, formed from Na+ and O2-?
- Na2O
- Charges must balance so 2 sodium ions are required
What is the chemical formula of magnesium hydroxide, formed from Mg2+ and OH-?
- Mg(OH)2
- Charges must balance so 2 hydroxide ions are required.
What is a covalent bond?
A bond formed when an electron pair is shared between two atoms.