Advertisements
Advertisements
प्रश्न
Explain the following reaction with the balanced equation.
Sodium burns in air
उत्तर
On burning, sodium metal combines with oxygen in the air to form sodium oxide.
\[\ce{\underset{\text{Sodium}}{4Na_{(s)}} + \underset{\text{Oxygen}}{O_{2(g)}} -> \underset{\text{Sodium oxide}}{2Na2O_{(s)}}}\]
APPEARS IN
संबंधित प्रश्न
What do you observe when silver nitrate is added to a solution of sodium chloride?
What do you observe when ferrous sulphate solution is added to an aqueous solution of sodium hydroxide.
Fill in the blank
When a piece of copper is added to silver nitrate solution, it turns ............in colour.
What do you observe when Magnesium ribbon is burnt in oxygen.
Write chemical equation for the event.
Iron filings are dropped in aqueous solution of copper sulphate.
Give a balanced equation for the reversible catalytic reaction involving nitrogen as one of the reactants.
Complete the statement by filling in the blank with the correct word:
The metal which reacts with steam and the reaction is reversible is ________.
Explain the following reaction with the balanced equation.
Magnesium reacts with dil HCl
Explain the following reaction with the balanced equation.
Sulphur burns in air
Which among the following alloys contain mercury as one of its constituents?
A metal A, which is used in thermite process, when heated with oxygen gives an oxide B, which is amphoteric in nature. Identify A and B. Write down the reactions of oxide B with HCl and NaOH.
A metal that exists as a liquid at room temperature is obtained by heating its sulphide in the presence of air. Identify the metal and its ore and give the reaction involved.
An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify A, B and C and give the reactions involved.
A metal M does not liberate hydrogen from acids but reacts with oxygen to give a black colour product. Identify M and black coloured product and also explain the reaction of M with oxygen.
A solution of CuSO4 was kept in an iron pot. After few days the iron pot was found to have a number of holes in it. Explain the reason in terms of reactivity. Write the equation of the reaction involved.
Give the steps involved in the extraction of metals of low and medium reactivity from their respective sulphide ores.
Explain the following
- Reactivity of Al decreases if it is dipped in HNO3
- Carbon cannot reduce the oxides of Na or Mg
- NaCl is not a conductor of electricity in solid state whereas it does conduct electricity in aqueous solution as well as in molten state
- Iron articles are galvanised.
- Metals like Na, K, Ca and Mg are never found in their free state in nature.
Arrange the following as per the instruction given in the bracket:
Al, K, Mg, Ca (decreasing order of its reactivity)
Three metal samples of magnesium, aluminium and iron were taken and rubbed with sandpaper. These samples were then put separately in test tubes containing dilute hydrochloric acid. Thermometers were also suspended in each test tube so that their bulbs dipped in the acid. The rate of formation of bubbles was observed. The above activity was repeated with dilute nitric acid and the observations were recorded.
Answer the following questions:
(i) When the activity was done with dilute hydrochloric acid, then in which one of the test tubes was the rate of formation of bubbles the fastest and the thermometer showed the highest temperature?
(ii) Which metal did not react with dilute hydrochloric acid? Give reason.
(iii) Why is hydrogen gas not evolved when a metal reacts with dilute nitric acid? Name the ultimate products formed in the reaction.
OR
Name the type of reaction on the basis of which the reactivity of metals is decided. You have two metals X and Y. How would you decide which is more reactive than the other?
