Why are the conductors of electric heating devices, such as bread-toasters
The heating element of an electric heater is made up of alloys because
Alloys have very high resistance, so when the current passes through the alloy, it offers great resistance.
The high resistance produces heat, which is required in such appliances.
If the heating elements were made of pure metal, they would have low resistance.
So, they will pass all the current flowing through it and hence would not produce heat.