Advertisements
Advertisements
Question
Fill in the blank
A change in which the substance can be brought back to its original state is called a _______ change.
Advertisements
Solution
A change in which the substance can be brought back to its original state is called a reversible change.
APPEARS IN
RELATED QUESTIONS
The chemical name of baking soda is ______.
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 |
Is kerosene an electrolyte or a non-electrolyte ?
Fill in the blank
A new substance is formed in a _______ change.
Balancing a chemical equation is based on
A solution of a substance ‘X’ is used for white washing write the reaction of the substance ‘X’ named in (a) above with water.
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
The spoiling of food is a chemical change which is recognized from the generation of certain ______ due to it.
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
Chlorine (Cl2) molecule is formed by ______ of electrons between two chlorine atoms.
Explain by writing a word equation.
Bubbles are seen on adding lemon juice to baking soda.
Give an example of a reaction where the following are involved:
Close contact
Write the chemical reaction where the following changes are observed.
Physical state is changed
Multiple choice:
Thermal decomposition of sodium carbonate will produce
Write your observation and a balanced equation in the case of the following substances being heated.
Ammonium chloride
Give a word equation for the following reaction.
A compound which on heating shows – colour change from brown to yellow.
________ is a chemical substance which alters the speed of a chemical reaction.
Classify the following processes into physical or chemical changes:
- Beating of aluminium metal to make aluminium foil.
- Digestion of food.
- Cutting of a log of wood into pieces.
- Burning of crackers.
Magnesium + oxygen → magnesium oxide.
2Mg + O2 → 2Mg O
Photosynthesis is a chemical charge. Justify your answer.
The reaction of H2 gas with oxygen gas to form water is an example of ______.
