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प्रश्न
Consider the following chemical equation I and II
- \[\ce{Mg + 2HCl -> MgCl_2 +H_2}\]
- \[\ce{NaOH +HCl -> NaCl + H_2O}\]
The correct statement about these equations is:
विकल्प
'I' is a displacement reaction and 'II' is a decomposition reaction.
'I' is a displacement reaction and 'II' is double displacement reaction.
Both 'I' and 'II' are displacement reactions.
Both 'I' and 'II' are double- displacement reactions.
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उत्तर
'I' is a displacement reaction and 'II' is double displacement reaction.
Explanation:
\[\ce{Mg(s) + 2HCl(aq) ->MgCl_2(aq) + H_2(g)}\]
Magnesium displaces hydrogen in a chloride molecule in a single displacement reaction because it is more reactive than hydrogen.
\[\ce{NaOH(aq) + HCl(aq) -> NaCl(aq) + H_2O(l)}\]
The reactants in a double displacement reaction exchange ions to create new molecules. The formation of salt (NaCl) and water (HOH) in the reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) is an example of a double displacement reaction, more precisely a neutralisation reaction.
संबंधित प्रश्न
What type of reaction is represented by the following equation?
\[\ce{2Na + 2H2O -> 2NaOH + H2}\]
A strip of metal X is dipped in a blue coloured salt solution YSO4. After some time, a layer of metal Y from the salt solution is formed on the surface of metal strip X. Metal X is used in galvanisation whereas metal Y is used in making electric wires. Metal X and metal Y together form an alloy Z.
- What could metal X be?
- What could metal Y be?
- Name the metal salt YSO4.
- What type of chemical reaction takes place when metal X reacts with salt solution YSO4? Write the equation of the chemical reaction involved.
- Name the alloy Z.
When a black metal compound XO is heated with a colourless gas Y2, then metal X and another compound Y2O are formed. Metal X is red-brown in colour which does not react with dilute acids at all. Gas Y2 can be prepared by the action of a dilute acid on any active metal. The compound Y2O is a liquid at room temperature which can turn anhydrous copper sulphate blue.
- What do you think is metal X?
- What could be gas Y2?
- What is compound XO?
- What is compound Y2O?
- Write the chemical equation of the reaction which takes place on heating XO with Y2.
- What type of chemical reaction is illustrated in the above equation?
When a strip of red-brown metal X is placed in a colourless salt solution YNO3 then metal Y is set free and a blue coloured salt solution X(NO3)2 is formed. The liberated metal Y forms a shining white deposit on the strip of metal Х.
- What do you think metal X is?
- Name the salt YNO3.
- What could be metal Y?
- Name the salt X(NO3)2.
- What type of reaction takes place between metal X and salt solution YNO3?
Explain the following type of chemical reaction, giving two examples for it:
Displacement reaction
Give reasons for the following:
The reaction of iron (III) oxide [Fe2O3] with heated aluminum is used to join cracked machine parts.
Classify the following reaction into –
- Direct combination
- Decomposition
- Displacement
- Double decomposition
The reaction is – Zinc reacts with copper [II] sulphate to give zinc sulphate and copper.
\[\ce{Pb + CuCl2 -> PbCl2 + Cu}\]
The above reaction is an example of:
Complete the following chemical reaction:
\[\ce{CuSO4 (aq) + Pb (s) -> \underline{}\underline{}\underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{}\underline{}\underline{}}\]
Name the chemical reaction type.
The colour of the solution observed after 30 minutes of placing zinc metal in copper sulphate solution is ______.
