Science Question Answer (5 Marks)

Metals: Metals are the elements which lose electrons to form cations and are electropositive in nature. For example, Sodium, potassium, Iron, Zinc and Calcium are metals. Metals are good conductors of heat and electricity. Metals are highly malleable and ductile.Copper, Aluminium, Mercury and sodium are metals.
Nonmetals: Nonmetals are the elements that gain electrons and form negative ions. They are also called electronegative elements. For example, chlorine, sulphur, oxygen, bromine, phosphorus and nitrogen are nonmetals. Nonmetals are not malleable and ductile but they are brittle. Nonmetals are bad conductors of heat and electricity. They have low melting and boiling points and are soft.Sulphur, Oxygen, Nitrogen and Chlorine are nonmetals.
Metalloids: The elements whose properties are intermediate between the properties of metals and nonmetals are called Metalloids. For example, Boron, Silicon and Germanium are metalloids. Heat and electricity can pass through metalloids but not as easily as in metals. Metalloids are also called semiconductors.Silicon and Germanium are metalloids.

Nonmetals are the elements that gain electrons and form negative ions. They are also called electronegative elements. For example, chlorine, Sulphur, oxygen, bromine, phosphorus and nitrogen are nonmetals. Nonmetals are not malleable and ductile but they are brittle. Nonmetals are bad conductors of heat and electricity. They have low melting and boiling points and are soft. Sulphur, Oxygen, Nitrogen, Fluorine and Chlorine are nonmetals.

The five uses of metals are given below:

1. Used for making machinery and heavy equipment. Ex - Iron.
2. Used in making electric wires because it is a good conductor of electricity. Ex- copper
3. Used to make thin foils for packaging medicines, chocolate, and food items. This is because it provides a complete barrier to light, oxygen, moisture, and bacteria.
4. Used in the manufacture of many products such as paints, rubber, cosmetics, pharmaceuticals, plastics, inks, soaps, batteries, textiles and electrical equipment.
5. Mercury is a liquid metal and is used for making thermometers. It is liquid at room temperature and is a very good conductor of heat.

The five uses of non-metals are given below:

1. Used for making fire crackers.
2. Oxygen is an essential non-metal for life. It helps in maintaining life and is inhaled during breathing.
3. Chlorine is used in water purification process to make drinking water supply germfree. Chlorine kills pathogens such as bacteria and viruses by breaking the chemical bonds in their molecules.
4. Iodine is a non-metal. It is used to make purple coloured solution which is applied on cuts and wounds as an antiseptic.
5. Nitrogen is also a non-metal is used to make fertilizers and explosives.

Metals are the elements which lose electrons to form cations and are electropositive in nature. For example, Sodium, potassium, Iron, Zinc and Calcium are metals. Metals are good conductors of heat and electricity. Metals are highly malleable and ductile. Nonmetals are the elements that gain electrons and form negative ions. They are also called electronegative elements. For example, chlorine, sulphur, oxygen, bromine, phosphorus and nitrogen are nonmetals.
Nonmetals are not malleable and ductile but they are brittle. Nonmetals are bad conductors of heat and electricity. They have low melting and boiling points and are soft. Following are the difference in chemical properties between metals and nonmetals.

S.No	Nonmetals	Metals
1.	Nonmetals form acidic or neutral oxides when they react with oxygen.	Metals react with oxygen to form metal oxides which are basic in nature.
2.	Nonmetals do not displace hydrogen with dilute acids.	Metals displace hydrogen from dilute acids.
3.	Nonmetals do not react with water and steam.	Metals react with water and steam.
4.	Nonmetals form negative ions.	Metals form positive ions.

1. Metals: Metals are the elements which lose electrons to form cations and are electropositive in nature.

For example, Sodium, potassium, Iron, Zinc and Calcium are metals.

Following are characteristics of metals:

1. Metals are good conductors of heat and electricity.
2. Metals are highly malleable and ductile.
3. They have very high melting and boiling points.
4. Metal oxides are basic in nature.
5. Metals displace hydrogen from dilute acids.

2. Nonmetals: Nonmetals are the elements that gain electrons and form negative ions. They are also called electronegative elements.

For example, chlorine, sulphur, oxygen, bromine, phosphorus and nitrogen are nonmetals.

Following are the characteristics of nonmetals:

1. Nonmetals are not malleable and ductile but they are brittle.
2. They are bad conductors of heat and electricity.
3. They have low melting and boiling points and are soft.
4. They form acidic or neutral oxides when they react with oxygen.
5. Nonmetals do not displace hydrogen with dilute acids.

Metals are the elements which lose electrons to form cations and are electropositive in nature. For example, Sodium, potassium, Iron, Zinc and Calcium are metals. Metals are good conductors of heat and electricity. Metals are highly malleable and ductile. The property of metals which allows metals to be hammered into thin sheets is called Malleability. Due this unique property, metals can be flattened into thin sheets by hammering and rolling. The property by which iron metal can be hammered to make objects of different shapes such as axe, spade etc. is called Malleability. As a result of high malleability, iron can be flattened or beaten into thin sheets and desired objects can be made by using it. Sodium, Potassium, Copper, Aluminium, Mercury and sodium are metals.