Bonding Structure And Properties Of Matter Flashcards
Name three types of chemical bonds
Ionic, covalent and metallic
What are the particles like in an ionic bond?
Oppositely charged ions
What do atoms do in a covalent bond to get a full outer shell?
Share pairs of electrons
What particles are involved in metallic bonding
Positive ions and delocalised electrons
What type of bond is formed between a metal and a nonmetal
Ionic bonds
What type of bonding is forms between just nonmetals?
Covalent
What type of bonding occurs in metals and alloys?
Metallic
What type of bonding involves gain or loss of electrons
Ionic
What happens when a metal and a nonmetal form an ionic bond?
Electrons in the outer shell of the metal atom are transferred to the nonmetal
What is the group number if an element forms of -2 ion
6
If an atom loses two electrons to form an ion, what charge will the ions have?
2+
What happens to a metal when forming an ionic bond?
Loses electrons and becomes positively charged - size of a charge is the same as the number of electrons lost. AKA lose one electron= +1 loses two electrons = +2
What happens to a nonmetal when forming an ionic bond
Gains electrons and becomes negatively charged -size of the charged is the same as the number of electrons gained. AKA gain one election = -1 charge and gain two electrons = -2
Why do metals and nonmetals form ionic bonds?
To get a full outer shell and therefore have the electronic structure of a noble gas
How can the transfer of electrons when forming an ion be represented?
Dot And cross diagram is
What are the limitations of using dot and cross diagram to represent ionic compounds?
It does not show how the ions are arranged in the space and does not show structure in 3-D.
What type of bonding is likely to occur between group one and two metals with group 6 and seven nonmetals
Ionic
Describe how magnesium and oxygen form an ionic bond
Magnesium loses two electrons and forms of 2+ ion magnesium gains two electrons and forms of 2- ion
What is a type of force that exist between oppositely charged ions?
Electrostatic
What type of structure is found in ionic compounds
Giant lattice
Describe the bonding and structure in an ionic compound
Giant lattice
Strong electrostatic attraction between oppositely charged ions with the forces acting in all directions
How can the structure of sodium chloride be represented, what are the limitations?
Space fill model: shows relative sizes of ions and regular pattern but can only see outer layer.
Ball and stick model: shows all the ions, bonds aren’t represented by lines, don’t show outer electrons.
What must the charges do when working out the formula of an ionic compound?
Cancel out
Eg
Na(+) and Cl(-)is NaCl
Mg(2+) and Cl(-) need 2 of cl- to cancel out the 2+ from mg
What are the properties of ionic compounds?
have a high melting points/high boiling point
Can conduct when molten (melted so liquid) or when in solution (dissolved in water)
Why do ionic compounds have high melting points?
Due to the strong electrostatic attraction between oppositely charged ions, which requires a lot of energy to break
Why do ionic compounds conduct when melted or dissolved in water?
Ions are free to move,they can’t move when they’re solid, and can carry a charge.
How do you workout the empirical formula of ionic compounds from a diagram?
Work out the chargers on the ions and balance them out
A compound is made up of calcium ions and chloride what is it empirical formula?
Calcium is in group 2, so forms of, 2+ ion
Chloride in group 7 so forms of 1- ion
Need two chlorides to balance out the charge on the calcium
How are covalent bonds formed?
By sharing electrons
How many electrons does each atom donate in a single covalent bonds?
One
What is the strength of a covalent bond?
Strong
What are the two types of covalent structure?
Small molecules and giant covalent
How are covalent bonds represented in small molecules?
Dot And cross - shows electrons shared
Displayed formula - shows covalent bonds as lines
Space fill - shows arrangement of atoms in 3-D
What type of structure is shown? H-C-H
Displayed - it shows covalent bonds as single lines between atoms
What are the limitations of using a displayed formula?
Does not show 3-D structure
Does not show where the electrons in a covalent bonds have come from
What type of bonding do you get in polymers?
Covalent, where N is a large number this is polyethylene
How are the atoms links in a polymer?
By strong covalent bonds between the atoms
weak intermolecular forces between the polymer chains
What are the properties of small covalent molecules?
Low melting points/boiling points, therefore gases mostly at room temperature
do not conduct electricity
Why do small covalent molecules have low boiling points, are gases and evaporate easily?
They have a weak intermolecular forces, which don’t require much energy to break
What happens to the boiling point of simple covalent molecules with increasing size?
Increases because there are more of the weak intermolecular forces present