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प्रश्न
Why does aluminium not react with water under ordinary conditions?
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उत्तर
Aluminium does not react with water under ordinary conditions because of the presence of a thin but tough layer of aluminium oxide on its surface. This layer of aluminium oxide prevents it from reacting with water.
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संबंधित प्रश्न
Why are metals called electropositive elements?
Which of the following elements would yield an acidic oxide?
Na, S, C, K, H
Name two metals which can, however, liberate hydrogen gas from very dilute nitric acid.
Arrange the following metals in order of their chemical reactivity, placing the most reactive metal first:
Magnesium, Copper, Iron, Sodium, Zinc, Lead, Calcium
A copper plate was dipped in AgNO3 solution. After certain time, silver from the solution was deposited on the copper plate. State the reason why it happened. Give the chemical equation of the reaction involved.
Name two metals which cannot displace hydrogen from dilute acids.
Why is white phosphorus kept immersed under water?
Give one example, with equation, of the displacement of hydrogen by a metal from an acid.
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
CuSO4(aq) + Fe(s) → FeSO4(aq) + Cu(s)
FeSO4(aq) + Zn(s) → ZnSO4(aq) + Fe(s)
On the basis of the above reactions, indicate which is most reactive and which is least reactive metal out of zinc, copper and iron.
If A, B, C, D, E, F, G, H, I, J and K represent metals in the decreasing order of their reactivity, which one of them is most likely to occur in a free state in nature?
Rewrite the following statement by selecting the correct option.
A solution of Al2(SO4)3 in water is _____________.
Answer the following question:
An element X on reacting with oxygen forms an oxide X2O. This oxide dissolves in water and turns red litmus blue. State whether element X is metal or a non - metal. Explain with a proper example.
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?
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?
Generally metals react with acids to give salt and hydrogen gas. Which of the following acids does not give hydrogen gas on reacting with metals (except Mn and Mg)?
Generally, metals are solid in nature. Which one of the following metals is found in liquid state at room temperature?
