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Question
Fill in the blank:
The basic conditions necessary for a chemical reaction is _______
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Solution
The basic conditions necessary for a chemical reaction is close contact .
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MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Reduction is a chemical reaction in which there is
- removal of hydrogen
- removal of oxygen
- addition of oxygen
- none of these
Name the type of chemical reaction shown by the following equation:
NaOH + HCl → NaCl + H2O
| Reactants | Products | Type of chemical reaction |
| BaCl2(aq) + ZnSO4(aq) | H2CO3(aq) | Displacement |
| 2AgCl(s) | FeSO4(aq) + Cu(s) | Combination |
| CuSO4(aq) + Fe(s) | BaSO4↓ + ZnCl2(aq) | Decomposition |
| H2O(l) + CO2(g) | 2Ag(s) + Cl2(g) | Double displacement |
Give an example of a reaction where the following are involved:
Close contact
Give an example of a reaction where the following are involved
Catalyst
State the type of reactions for the following represent and balance the ones that are not balanced.
Cl2 + 2KBr → 2KCl + Br2
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\[\ce{Pb(NO3)2 ->[\Delta]}\]
Give a chemical test to distinguish between the following gases.
NH3 and HCl
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A coloured substance which leaves on strong heating a black residue and evolves two colourless gases one of which is acidic and the other neutral.
On heating which of the following substances i.e. copper carbonate, zinc carbonate, washing soda, copper sulphate, zinc nitrate, copper nitrate, lead nitrate, ammonium chloride and ammonium dichromate – relate to the reaction given below.
A coloured substance which leaves a black residue and evolves two gases one of which is acidic and coloured and the other neutral and colourless.
Give balanced equation for the following conversion affected by heat alone on the substance:
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Match the chemical reactions in List I with the appropriate answer in List II.
| List I | List II | ||
| 1. | \[\ce{XY⇌[heat]X + Y}\] | A: | Displacement reaction |
| 2. | \[\ce{XY->X + Y}\] | B: | Double decomposition |
| 3. | \[\ce{X+Y- + A+B^-->X+B- + A+Y-}\] | C: | Endothermic reaction |
| 4. | \[\ce{X + YZ->XZ + Y}\] | D: | Thermal dissociation |
| 5. | \[\ce{X + Y->[heat]XY -\Delta}\] | E: | Decomposition reaction |
Complete the statement by filling in the blank with the correct word:
The reddish-brown precipitate obtained during a double decomposition precipitation reaction between an iron salt and alkali is __________.
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Analogy:
H2O: Water:: NaCl: ______.
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Can you change rust back into iron by some simple method?
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When carbon dioxide is passed through lime water ______.
