SC5c properties of ionic compounds Flashcards
what are the properties of ionic compounds?
ionic substances form giant ionic lattices containing oppositely charged ions so they have a high melting and boiling point.
solids do not conduct electricity as it has fixed ions but aqueous do as the ions aren’t fixed.
core practical - how to identify ionic compounds (circuit)
~Choose one of the test substances
~Add one small spatula of solid or one pipette of ethanol to a boiling tube.
~Add water until the tube is about half full.
~Stopper the boiling tube and, with your thumb over the bung, shake the boiling tube.
~Observe and record whether the substance dissolves or not.
~If the substance dissolves, pour the solution into the beaker and add more water so that the beaker is about one-third full.
~Observe and record whether the lamp lights or not.
Magnesium chloride is an ionic compound and has a high melting point.
Explain why magnesium chloride has a high melting point.
(3 marks)
There is a strong force of attraction (1)
between oppositely charged ions (1)
so a lot of energy is needed to separate the ions (1)
