Question

An industrial chemist is studying a sample of an unknown metal. Describe two ways he could change the metal physically and two ways he could change the metal chemically to try to identify it.

Answer 1

- heat the metal until melts (physical change)

- attempt to react the metal with oxygen (chemical change)

- stretch the metal into a wire (physical change)

- attempt to react the metal with acid (chemical change)

Answer 2

Physical changes:

- Try to scratch with other metals to find the hardness
- Try to deform to find the maleability
- Heat it and measure the temperature to find the melting point

Chemical changes

- Put it in water to see if it reacts and if the reaction is violent (metals from group I and II react with water and Li, Na and K does it violently)

- Put it in acids of different strength, to observe if they react. Metals of second group react rapidly with acids. Other metals react only slowly with acids and others are almost inert.