Advertisements
Advertisements
प्रश्न
The elements whose oxides can turn litmus solution red are:
(a) lithium and sodium
(b) copper and potassium
(c) carbon and hydrogen
(d) phosphorus and sulphur
Advertisements
उत्तर
(d) phosphorus and sulphur
Phosphorus and sulphur are non-metals whose oxides are acidic in nature. These oxides turn blue litmus solution to red.
APPEARS IN
संबंधित प्रश्न
Metal A has electronic configuration (2, 8, 1) and metal B has (2, 8, 8, 2). Which is more reactive? Why? Identify these metals.
‘E’ is an element which reacts with oxygen to form an oxide E2O. An aqueous solution of E2O turns red litmus blue, so:
i. What is the nature of oxide E2O ?
ii. Write the name of element ‘E’.
Which gas is produced when dilute hydrochloric acid is added to a reactive metal?
Write the electron-dot structures for sodium, oxygen and magnesium.
Food cans are coated with tin and not with zinc because ______.
Write equation for the reaction of sodium with oxygen.
Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.
Complete and balance the following equation:
Cu (NO3)2 (aq) + Zn(s) →
Name two metals which can, however, liberate hydrogen gas from very dilute nitric acid.
What happens when calcium reacts with chlorine? Write an equation for the reaction which takes place
What is the action of water on aluminium ? Write equation of the chemical reaction involved.
You are given samples of three metals − sodium, magnesium and copper. Suggest any two activities to arrange them in order of their decreasing reactivities.
What happens when a metal reacts with dilute hydrochloric acid? Explain with the help of an example.
Write the equation for the reaction of Magnesium with dilute hydrochloric acid.
Name the products formed. Also indicate the physical states of all the substances involved.
One of the following is not a neutral oxide. This is:
(a) CO
(b) H2O
(c) N2O
(d) Na2O
An element X forms two oxides XO and XO2. The oxide XO is neutral but XO2 is acidic in nature. The element X is most likely to be:
(a) sulphur
(b) carbon
(c) calcium
(d) hydrogen
Which one of the following four metals would be displaced from the solution of its salt by the other three metals?
(a) Zn
(b) Ag
(c) Cu
(d) Mg
What is the characteristic of the electronic configuration of noble gases?
Write the chemical equation of the above process.
A cable manufacturing unit tested few elements on the basisof their physical properties.
| Properties | W | X | Y | Z |
| Malleable | Yes | No | No | Yes |
| Ductile | Yes | No | No | Yes |
| Electrical conductivity | Yes | Yes | Yes | No |
| Melting Point | High | Low | Low | High |
Which of the above elements were dicarded for usage by the company?
