Ionic, Covalent & Metallic Bond Flashcards

All 30 cards in this deck

What are the three types of strong chemical bond?

Ionic, covalent and metallic.

Which type of bonding occurs in compounds formed from a metal combined with a non-metal?

e.g. magnesium oxide

Ionic bonding.

Which type of bonding occurs in most non-metallic elements and in compounds of non-metals?

e.g. $\mathrm{Cl_2}$ and $\mathrm{CO_2}$

Covalent bonding.

Which type of bonding occurs in metallic elements and alloys?

e.g. copper and brass

Metallic bonding.

Which particles are involved in covalent bonding, and what do they do with electrons?

Atoms, which share pairs of electrons.

What type of force holds the particles together in ionic, covalent and metallic bonding?

Electrostatic forces of attraction.

Which particles are the bonding particles in ionic bonding?

Oppositely charged ions.

What happens to electrons when a metal atom reacts with a non-metal atom?

Electrons in the outer shell of the metal atom are transferred to the non-metal atom.
The metal atom becomes a positive ion; the non-metal atom becomes a negative ion.

What is the charge on the ions formed by metals in Group 1 and in Group 2?

Group 1: $1+$; Group 2: $2+$.
e.g. $\mathrm{Na^+}$ and $\mathrm{Mg^{2+}}$

What is the charge on the ions formed by non-metals in Group 6 and in Group 7?

Group 6: $2-$; Group 7: $1-$.
e.g. $\mathrm{O^{2-}}$ and $\mathrm{Cl^-}$

What electronic structure do the ions of Group 1, 2, 6 and 7 elements have?

The electronic structure of a noble gas (Group 0) — a full outer shell.

What are the steps to draw a dot and cross diagram for the formation of an ionic compound?

e.g. sodium reacting with chlorine

1. Draw the outer shell electrons of each atom: Na has 1, Cl has 7.
2. Transfer the electron(s) from the metal to the non-metal so both have full outer shells.
3. Draw each ion in square brackets with its charge: $[\mathrm{Na}]^+$ and $[\mathrm{Cl}]^-$.

True or false? When an ionic compound forms, the non-metal atoms lose electrons.

False. Non-metal atoms gain electrons to become negatively charged ions; the metal atoms lose electrons.

What type of structure does an ionic compound have?

A giant structure (lattice) of ions.

What holds an ionic compound together, and in which directions do these forces act?

Strong electrostatic forces of attraction between oppositely charged ions, acting in all directions in the lattice.

What are the steps to work out the empirical formula of an ionic compound from a model of its lattice?

e.g. a model showing 4 $\mathrm{Mg^{2+}}$ ions and 4 $\mathrm{O^{2-}}$ ions

1. Count the ions of each type: 4 and 4.
2. Write the simplest whole number ratio: $1:1$.
3. Write the formula with the positive ion first: $\mathrm{MgO}$.

Give one limitation of using a dot and cross diagram to represent a giant ionic structure.

It shows electron transfer but not the giant three-dimensional arrangement, sizes or spacing of the ions.

Give one limitation of using a ball and stick model to represent a giant ionic structure.

It shows gaps (sticks) between ions that are not really there, and only a small part of the lattice, not to scale.

True or false? Sodium chloride is made up of separate NaCl molecules.

False. Sodium chloride is a giant ionic lattice of $\mathrm{Na^+}$ and $\mathrm{Cl^-}$ ions; NaCl is its empirical formula.

What is a covalent bond?

A shared pair of electrons between two atoms.

What are the steps to draw a dot and cross diagram for a small covalent molecule?

e.g. water, $\mathrm{H_2O}$

1. Count the outer shell electrons: O has 6, each H has 1.
2. Overlap the shells so each shared pair completes the outer shells: O shares one pair with each H.
3. Show the result: 2 bonding pairs in the overlaps and 2 non-bonding pairs on the oxygen.

What three kinds of structure can covalently bonded substances have?

Small molecules, very large molecules such as polymers, and giant covalent structures such as diamond and silicon dioxide.

In a displayed (line) structure of a molecule, what does one line between two atoms represent?

A single covalent bond — one shared pair of electrons.

What are the steps to deduce the molecular formula of a substance from a dot and cross or ball and stick diagram?

e.g. a diagram showing 3 carbon, 6 hydrogen and 1 oxygen atom

1. Count the atoms of each element: C 3, H 6, O 1.
2. Write the symbols with the numbers of atoms as subscripts (no number for 1): $\mathrm{C_3H_6O}$.

True or false? The covalent bonds between the atoms inside a small molecule are weak.

False. Covalent bonds between atoms are strong.

What type of structure do metals consist of?

Giant structures of atoms arranged in a regular pattern.

What happens to the electrons in the outer shell of metal atoms in a metallic structure?

They are delocalised, so they are free to move through the whole structure.

What gives rise to strong metallic bonds?

The sharing of delocalised electrons between the metal atoms.

True or false? In metallic bonding, electrons are transferred from one metal atom to another.

False. The outer electrons are delocalised and shared throughout the whole structure.

True or false? Polymers are covalently bonded substances made of very large molecules.

True. Some covalently bonded substances have very large molecules, such as polymers.