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प्रश्न
Name the following:
The type of change physical or chemical involved – ‘during respiration in human beings’.
उत्तर
Chemical Change.
APPEARS IN
संबंधित प्रश्न
Give reason .
A person suffering from acidity is advised to take an antacid.
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Reduction reaction is the exact opposite of
- displacement reaction
- decomposition reaction
- oxidation reaction
- none of these
MATCH THE COLUMNS
| 1 . `H_2` + `CI_2` `→` 2HCI | a. displacement reaction |
| 2. `2FeCI_3`+ `H_2` `→` `2FeCI_2` +2HCI` | b. addition of an electronegative redical |
| 3. Fe + `CuSO_4` `→``FeSO_4` +Cu` | c. removal of an electronegative redical |
| 4. `2H_2O` +`4NO_2`+`O_2` `→` `4HNO_3` | d.reduction by adding hydrogen |
| 5. 3Fe +`3CI_2` `→` `2FeCI_3` | e.electrolysis of water |
| 6. `FeCI_3`+ 3NaOH `→``Fe(OH)_3``↓`+NaCI | F.double decomposition,precipitation reaction |
| 7.`2H_2O` `→` `2H_2``↑`+`O_2` | e. combination or synthesis reaction |
Define chemical reaction.
Write balanced chemical equations for the reactions represented by word equations in the conditions for chemical reaction.
Balance the following equation :
Fe + H2O → Fe3O4 + H2
State what you would observe when the following substance is heated in a glass test tube Copper (II) carbonate Red lead .
| 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 |
State the type of reactions for the following represent and balance the ones that are not balanced.
Cl2 + 2KBr → 2KCl + Br2
Give an example of the following chemical changes.
A reaction involving
(i) Change of state
(ii) formation of precipitate
Give a chemical test to distinguish between the following gases.
CO2 and SO2
Give a chemical test to distinguish between the following gases.
HCl and H2S
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.
Complete the table given below.
| Addition of dil. H2SO4 to zinc | Test for gas evolved |
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Lead nitrate.
What is the role of a catalyst in a chemical reaction?
Which of the following is not an “element + element → compound” type reaction?
The changes in which new substance with new chemical properties are formed are ______.
Which of the following statement is incorrect for a chemical reaction?
Melting of wax is a change where a solid changes to a liquid state. Give one more such change which you observe in your surroundings
Write word equations for two chemical reactions with the help of materials given in the box.
Air, copper sulphate, iron, vinegar, iron oxide, carbon dioxide, iron sulphate, copper, lime water, water
A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
Are these changes chemical in nature?
Is the conversion of milk into ice cream a chemical change?
Photosynthesis is a chemical charge. Justify your answer.
______ is the chemical name of slaked lime.
______ is the chemical name of limestone.
Acid rain is a result of ______.
Write the effects of chemical reactions.
