Metal react with oxygen to produce _________oxides and non-metal react with oxygen to produce_________oxides.
The presence of _________ and _________are necessary for iron to rust.
_________is used for making X-ray shields.
_________non-metals is used in fluorescent bulbs to display advertisements.
_________element is used for making pencil lead.
_________and _________are lustrous non-metals.
_________is the only non-metals that exist as liquid at room temperature.
The property of metals by which it can be beaten into sheets is called_________
_________metal can be cut with knife.
_________non-metal is used for vulcanisation of rubber.
_________metal is used in processed food packaging.
Process of coating metals with zinc is called_________
Elements that possess properties of both metals and non-metals are called_________
_________is a pure chemical substance consisting of only one type of atoms.
Metal react with dilute acids to form_________ and_________
1. Basic, acidic
2. Air, water
6. Graphite, iodine
15. Salt, hydrogen gas
Gold does not easily react with other substances. It is an unreactive metal and once polishes, it retains their shine for a long time, therefore, it is used for making jewellery.
Corrosion is used to describe the process by which minerals such as metals are slowly eaten away when exposed to air and moisture.
No gas is releases when sulphur is added to dilute HCl because non-metals do not react with dilute HCl and sulphur is a non-metal.
Since copper is a good conductor of electricity, it is used in electrical cables.
Copper vessel gets corroded in the presence of moist air that is carbon dioxide and water to form green coating of a substance called basic copper carbonate.
Silicon is considered to be the backbone of electronics industry.
Sodium metal which react vigorously with the oxygen present in air at room temperature to form sodium oxide. Hence, sodium is stored under kerosene to prevent its reaction with oxygen and moisture present in air.
Metal oxides formed are basic in nature, when dissolved in water they form bases which turn red litmus into blue whereas non-metal oxides are acidic in nature, when dissolve in water they form acids which turn blue litmus into red.
Silver does not get easily corroded in unpolluted air, however, if the air is polluted with sulphur compounds such as hydrogen sulphide then silver reacts with it to form a black coating of silver sulphide.
Silver and gold are present at the bottom of the reactivity series of metals. They are unreactive metals and do not react with water, acids and alkalis. They therefore, occur n free state in nature. So they are noble metals.
Copper is the metal other them iron which gets rusted in moist air.In the presence of carbon dioxide and water, copper gets corroded or rusted to form a green coating. This green coating is a mixture of copper hydroxide and copper carbonate.
(b) Iron and chromium
(d) Nitrogen and Phosphorous
5. aluminium foil
6. sodium ,potassium and mercury
8. Sodium, potassium, kerosene.
11. iodine and graphite
This metals and non metals class 8 questions is prepared keeping in mind the latest syllabus of CBSE . This has been designed in a way to improve the academic performance of the students. If you find mistakes , please do provide the feedback on the mail.