Determining Structure and Bonding
Why does Sodium metal conduct electricity when solid sodium chloride only conducts when molten or in solution ❓
Sodium chloride only conducts when molten or in a solution because the as the ionic bonds are rigid and so not allow for the free flow of electrons
In a solution or molten the bonds are loser and the electrons can move more freely allowing them to carry the charge
Sodium metal conducts electricity because the sea of delocalized electrons are able to transfer the charge through the metal
Why is carbon dioxide a gas at room temperature but silicon dioxide is a solid?
Silicon dioxide is a giant covalent structure, there is much more energy needed to break the strong bonds of silicon dioxide compared to the bonds of CO2
Silicon dioxide has much stronger intermolecular forces of attraction is also has a higher boiling and melting point compared to CO2
Carbon dioxide is a gas at rtp because it has a low boiling point that is below 23 degrees Celsius also because there are weak intermolecular forces of attraction which can be easily overcome by the room temperature
Why is ethanol a liquid at room temp but ethane is a gas?
why does ice float on water?
Ethane is non-polar (no H bonds) so the molecules are free and fly apart
Ethanol is a polar molecule so it forms a chain which become entangled and cannot move very faar from each other
Ethanol has a lager molecular mass than ethane making it heavier
Ice floats on water because it is less dense than water
Why is aluminum a better electrical conductor than sodium?
Compared to the one electron on the outer shell of sodium which carries three times less charge
As there are more electrons on the aluminium it can carry more charge and therefore can conductor
Aluminium is better as it has three electrons on the outer shell of each atom
Why is iodine a solid at room temperature but chlorine is a gas?
Why is magnesium a solid at room temperature but ethane is a gas?
why do graphite and diamond both have high melting points but only graphite conducts electricity?
Graphite forms three covalent bonds so each carbon atom has a free (delocalised) electrons between the layers which can carry charge so it can conduct electricity
Diamonds form four covalent so there are no delocalised electrons therefore electricity cannot be conducted
Both have very strong covalent bonds
intermolecular forces are weak but collectively they are very strong and numerous forces between iodine molecules means more heat energy is needed to break the intermolecular forces and separate molecules
Chlorine does't have as many electrons so less intermolecular forces so collectively it is very weak, therefore less heat energy is required to break the bonds
Iodine has more electrons per molecule so it has more contact surfaces for intermolecular forces
Magnesium has strong intermolecular forces and requires enough energy to break the strong bonds and separate the molecules
The energy at room temp is not enough to break the bonds of magnesium so it remains a solid
but there is enough energy to break the forces in ethane to become a liquid and their is also enough energy to separate the molecules so it becomes a gas
Below 4 degrees water molecules start to lock into place, molecules become further apart as the ice begins to expand and the gaps are filled with air
Because the same mass of water is occupying more space it will float in liquid water