Chemical Changes Flashcards
Give the general word equation for the reaction between an acid and a base.
acid + base → salt + water
What type of reagent could be used to show that an acid or base has been completely neutralised?
Universal indicator
What is a strong acid?
A substance that completely ionises in water (dissociates to release H+ ions)
Is zinc more or less reactive than iron?
More reactive
What is the general word equation for the reaction of a metal with an acid?
acid + metal → salt + hydrogen
What product forms in the oxidation of magnesium by oxygen?
Magnesium oxide
Explain how you decide whether a metal can be extracted from its oxide by reduction with carbon.
If the metal is less reactive than carbon, it can be extracted with carbon.
In terms of electrons, give the definition of oxidation.
Loss of electrons
In a displacement reaction, does the metal atom get reduced or oxidised?
Reduced
During electrolysis, which electrode are the positive ions attracted to?
Negative electrode (cathode)
Why can ionic solids not undergo electrolysis?
Their ions are in fixed positions and can’t move
Do ions get reduced or oxidised at the anode?
Oxidised
During the manufacture of aluminium from bauxite, which electrode is aluminium found at?
Negative electrode (cathode)
In what situation will hydrogen gas be given out during the electrolysis of an aqueous solution of an ionic solid?
If H+ ions and metal ions are present and if the metal is more reactive than hydrogen.
