Metals and Non Metals

1. What happens when metals react with acids?

Most metals react with acids to generate hydrogen gas and salt. However, not all metals react the same way to acids. Salt and hydrogen gas are generated when an acid interacts with a metal.

For Example,

When zinc powder interacts with hydrochloric acid, H2 gas and zinc chloride are produced.

Zn (s) + 2HCl (aq)→ ZnCl₂ + H₂

The salt formed is determined by the reaction of acid and metal.

2. Give Reasons for Following:

1. School bells are made up of metals.
2. Electric wires are made up of copper.

1. It is because metals are sonorous, i.e. they produce sound when struck with a hard substance.
2. It is because copper is good conductor of electricity.

3. Give Reasons for Following

1. Aluminium oxide is considered an amphoteric oxide.
2. Ionic compounds conduct electricity in a molten state.

1. It is because it reacts with acids as well as bases to produce salts and water. ’Al’ is a less electropositive metal. So, it forms an amphoteric oxide which can react with acid as well as the base.
2. Ionic compounds can conduct electricity in a molten state because ions ’ become free to move in a molten state.

4. What are Amphoteric Oxides?

Those oxides which react with acids as well as bases to produce salts and water are called amphoteric oxides, e.g. Na₂O, ZnO, are amphoteric oxides.

5. What chemical name of the Coating that forms on silver and copper articles when these are left exposed to moist air?

Ag₂S (silver sulphide) is formed on silver, basic copper carbonate CuCO₃. Cu(OH)₂ is formed on copper.

Elements are chemically occurring natural substances that may be found in a free state or combined state. They are extracted from ores. ores are found deep inside the earth’s crust. The ores from which metals can be easily extracted are called minerals. By the definition of minerals, metals can be extracted. 

Based on their characteristics, elements are categorised as either metals or nonmetals. Much of the time, you can determine if an element is a metal by its metallic sheen, but this isn’t the sole distinction between these two broad categories of elements.