Bonding, Structure and Properties of Matter Flashcards
Why does an atom lose or gain electrons?
To get a full outer shell and be stable
What happens to a metal when it forms an ion?
They lose electrons to form positive ions
What happens to non metals when they form an ion
They gain electrons to form negative ions
If an atom lost 2 electrons to form an ion what would the charge be?
2+
If an atom gains 3 electrons when turning to an ion what would the charge be?
3-
What type of bonding occurs when a metal and non metal react together?
Ionic bonding
What is ionic bonding?
When non metals and metals react together
The metal atom loses electrons to form positively charged ion
The non metal atom gains these electrons to form negatively charged ion
What is the force called where oppositely charged ions are strongly attracted to each other?
Electrostatic forces
What charge will group 1 element ions have?
1+
What charge will group 2 element ions have?
2+
What charge will group 6 element ions have?
2-
What charge will group 7 element ions have?
1-
What diagrams show ionic bonding or ions?
Dot and cross diagrams
What must you always do when drawing an ion?
Use square brackets and state the charge
What is the structure of ionic compounds?
Giant ionic lattice
What are the properties of the ionic compound structure (giant regular lattice)?
Very strong electrostatic forces of attraction in all directions between oppositely charged ions
Properties of ionic compounds
High melting and high boiling points due to many strong bonds between ions.
When solid can’t conduct electricity as ions are held in place
When liquid will conduct electricity as ions are free to move
Dissolve easily in water- ions superstar and are free to move
What method do you use to write the empirical formula of an ionic compound?
Swap and drop
What is covalent bonding?
When two non metals react together and share electron pairs to make covalent bonds
How can you draw covalent bonds?
Dot and cross diagram
In shells
Line diagrams
What is a simple molecular substance?
A substance made up of molecules containing a few atoms joined together by covalent bonds.
Eg/ hydrogen ( needs two atoms of hydrogen in order to both have full outer shell through covalent bonds)
What are the properties of simple molecular substances?
Forces of attraction between molecules are very weak
Melting and boiling points are very low as molecules are easily parted from each other
Gases or liquids at room temperature
Don’t conduct electricity as there are no free electrons
What is a covalent bond?
A chemical bond made by the sharing of a pair of electrons between two atoms
In what states are most simple molecular substances at room temperature?
Gas or liquid
What forces are stronger in simple molecular substances? Covalent bonds or intermolecular forces?
Covalent bonds
What forces need to be overcome to boil a simple molecular compound?
Intermolecular forces
Why may hydrogen chloride have poor electrical conductivity?
It doesn’t contain any ions or delocalised electrons to carry a charge
Explain how the atoms are held together in a molecule of hydrogen chloride
A pair of electrons (one from hydrogen and one from chlorine) is shared between the two atoms.
The atoms the held together by the strong attraction between this shared pair of negatively charged electrons and the positively charged nuclei of the atoms.
Why may a substance have a higher boiling point than another substance?
They could be a larger molecule so the intermolecular forces are stronger between the bonds so it takes more energy to boil it, therefore the temperature is higher.
What is a polymer?
A long chain of repeating units
How do you draw a polymer?
Draw the shortest repeating section
How do you find the molecular formula of a polymer?
Write down the molecular formula in brackets and put an n outside of it
What state are polymers at room temperature?
Solid