Question

Why mixture does not have fixed melting or boiling point.give 2 reasons

Answer 1

Mixture contain different types of substances in different compositions. these substance may have different melting andboiling point hence the melting and boiling point of a mixture cannot be fixed. ... However there are also impurities can lowers the melting and boiling point during heating.

Answer 2

Mixtures have more than one substance inside it. When more solutes are present in a mixture, the melting and boiling point are changed. apc_128 is correct. If you heat salt water, the boiling point will exceed 100 Celcius. However there are also impurities can lowers the melting and boiling point during heating. Example, cryolite (Na3AlF6) are added to aluminium oxide when heating to turn it to molten form.