Advertisements
Advertisements
प्रश्न
The elements whose oxides can turn litmus solution blue are:
(a) carbon and sulphur
(b) sodium and carbon
(c) potassium and magnesium
(d) magnesium and sulphur
Advertisements
उत्तर
(c) potassium and magnesium
Potassium and magnesium are metals whose oxides are basic in nature. These oxides turn red litmus solution to blue.
APPEARS IN
संबंधित प्रश्न
Write equations for the reactions of calcium and potassium with water.
What would you observe when zinc is added to a solution of iron (II) sulphate? Write the chemical reaction that takes place.
Differentiate between metal and non-metal on the basis of their chemical properties.
The solution of Aluminium sulphate in water is .....................
(a) Green
(b) Colourless
(c) Pink
(d) Blue
Why are metals called electropositive elements whereas non-metals are called electronegative elements?
What name is given to those metal oxides which show basic as well as acidic behaviour?
Name the metal which has been placed at the bottom of the reactivity series.
Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.
What happens when magnesium reacts with very dilute nitric acid? Write an equation for the reaction involved.
Which gas is produced when dilute hydrochloric acid is added to a reactive metal?
Name another metal oxide which behaves like aluminium oxide.
Write the equation for the reaction of Iron with dilute hydrochloric acid.
Name the products formed. Also indicate the physical states of all the substances involved.
An acidic oxide is produced by the element:
(a) Na
(b) C
(c) Ca
(d) H
The least reactive metal among the following is:
(a) sodium
(b) silver
(c) copper
(d) lead
An element E reacts with water to form a solution which turns phenolphthalein solution pink. The element E is most likely to be:
(a) S
(b) Ca
(c) C
(d) Ag
An element E forms an oxide E2O. An aqueous solution of E2O turns red litmus paper blue.
(a) What is the nature of the oxide E2O?
(b) State whether element E is a metal or a non-metal.
(c) Give one example of an element like E.
State and explain the reaction, if any, of the following metals with a solution of copper sulphate:
(a) Gold
(b) Copper
(c) Zinc
(d) Mercury
Write the chemical equation of the above process.
Write the chemical equation for the following reaction:
Cinnabar is heated in the presence of air.
