Three reactions are given below. Which of them is/are correct?
Generally, non-metals are not lustrous. Which of the following non-metal is lustrous?
Which of the following non-metals exist in liquid state at room temperature?
Which of the following metals form an amphoteric oxide?
Which of the following non-metal is an exception which can conduct electricity?
Which of the following properties is NOT exhibited by ionic compounds?
What happens when calcium is treated with water?
(i) It does not react with water
(ii) It reacts violently with water
(iii) It reacts less violently with water
(iv) Bubbles of hydrogen gas formed stick to the surface of calcium
Calcination and roasting are the processes used in extraction of metals. How are these processes different?
State whether TRUE or FALSE.
When metals are treated with acids, hydrogen gas is liberated.
Which of the following option is used with aluminium in joining the railway tracks?
Which of the following is an ore of mercury?
What are minerals?
State whether the given statement is TRUE or FALSE.
A natural rock containing one or more minerals is called ore.
Calcination involves heating a carbonate-containing ore at a high temperature in the presence of limited air to produce metal oxide.
The metal reacts with moisture or air to produce the metal oxide which deteriorate the quality of metal. This is called _______________ (corrosion/galvanisation)
Gangue is the impurity present in the ore.
Chemical decomposition in the presence of electric current is called as ________________ (electrolysis/calcination)
A non-metal ‘X’ is a major constituent of our food and forms two oxides ‘Y’ and ‘Z’. Oxide ‘Y’ is toxic and causes suffocation whereas Z causes global warming.
Identify X, Y and Z.
Which of the following chemical equations represents the correct chemical reaction for roasting of zinc ore?
An unknown element forms an oxide that is acidic in nature. The unknown element is ________________ (metal/non-metal)
A solution of Copper sulphate was kept in an iron pot. After few days the iron pot was found to have a number of holes in it. Which of the following is the correct reason behind this?