Advertisements
Advertisements
प्रश्न
What are noble gases
Advertisements
उत्तर
The elements in group 18 of the periodic table, which do not combine with other elements are known as noble gases. These elements are helium, neon, argon, krypton, xenon and radon.
APPEARS IN
संबंधित प्रश्न
A student added few pieces of aluminium metal to two test tubes A and B containing aqueous solutions of iron sulphate and copper sulphate. In the second part of her experiment, she added iron metal to another test tubes C and D containing aqueous solutions of aluminium sulphate and copper sulphate.
In which test tube or test tubes will she observe colour change? On the basis of this experiment, state which one is the most reactive metal and why.
Name the metal which has been placed just below copper in the reactivity series.
Complete and balance the following equation:
Na2O + H2O →
Complete and balance the following equation:
Cu (NO3)2 (aq) + Zn(s) →
How do metals react with hydrogen? Explain with an example.
What happens when calcium reacts with chlorine? Write an equation for the reaction which takes place
Arrange the following metals in order of their chemical reactivity, placing the most reactive metal first:
Magnesium, Copper, Iron, Sodium, Zinc, Lead, Calcium.
What happens when calcium reacts with water? Write the chemical equation of the reaction of calcium with eater.
Name one metal which displaces copper from copper sulphate solution and one which does not.
An element X reacts with hydrogen, when heated, to form a covalent hydride H2X. If H2X has a smell of rotten eggs, the element X is likely to be:
(a) carbon
(b) sulphur
(c) chlorine
(d) phosphorus
An element is soft and can be cut with a knife. If is very reactive and cannot be kept open in the air. It reacts vigorously with water. The element is most likely to be:
(a) Mg
(b) S
(c) P
(d) Na
An element X forms two oxides XO and XO2. The oxide XO has no action on litmus solution but oxide XO2 turns litmus solution red.
(a) What is the nature of oxide XO?
(b) What is the nature of oxide XO2?
(c) Would you call element X a metal or a non-metal? Give reason for your choice.
(d) Can you give an example of element like X?
Which of the following reactions will not occur? Why not?
(a) MgSO4 (aq) + Cu (s) → CuSO4 (aq) + Mg (s)
(b) CuSO4 (aq) + Fe (s) → FeSO4 (aq) + Cu (s)
(c) MgSO4 (aq) + Fe (s) → FeSO4 (aq) + Mg (s)
In nature, metal A is found in a free state while metal B is found in the form of its compounds. Which of these two will be nearer to the top of the activity series of metals?
Name a metal which does not react with cold as well as hot water but reacts with steam.
Arrange the following metals in the increasing order of their reactivities:
Copper, Zinc, Aluminium, and Iron
Which one among the following is an acidic oxide?
An element X is soft and can be cut with a knife. This is very reactive to air and cannot be kept open in the air. It reacts vigorously with water. Identify the element from the following.
An alkali metal A gives a compound B (molecular mass = 40) on reacting with water. The compound B gives a soluble compound C on treatment with aluminium oxide. Identify A, B and C and give the reaction involved.
The substance that will be flattened on beating with a hammer is ______.
