Advertisements
Advertisements
प्रश्न
Write true or false :
No new substance is formed during a chemical reaction.
विकल्प
True
False
Advertisements
उत्तर
False
APPEARS IN
संबंधित प्रश्न
How do the following help in bringing about a chemical change?
light.
Fill in the blanK
A .............is a substance which changes the rate of a chemical reaction without undergoing a chemical change.
TRUE \ FALSE
Ammonia is a good oxidizing agent.
TRUE \ FALSE
Electrolytic refining is a method in which a thin coating of a metal is done over another metal.
TRUE \ FALSE
Evaporation of water is a physical change. True or false ?
Write balanced chemical equations for the reactions represented by word equations in the conditions for chemical reaction.
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)
A colourless solution of calcium hydroxide in a test tube turns ______ on blowing in it through a blow tube for some time.
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)
Oxygen is a ______ in respiration.
Explain by writing a word equation.
Limestone powder disappears on adding to dilute hydrochloric acids.
State the main characteristics of chemical reactions. Give at least one example in each case.
Complete the following table and write your observations.
|
Hydrogen sulphide |
Ammonia |
Sulphur dioxide |
Hydrogen chloride |
|
|
Shake the gas with red litmus solution |
||||
|
Shake the gas with blue litmus solution |
||||
|
Apply a burning splint to a gas |
What do you observe when dilute sulphuric acid is added to the following:
Sodium Sulphide
Give balanced equation for the following conversion affected by heat alone on the substance:
Zinc nitrate to nitrogen dioxide
What happens when cane sugar is strongly heated? Mention any two changes in it.
______ is not a chemical change.
Which of the following are chemical changes?
(i) Decaying of wood
(ii) Burning of wood
(iii) Sawing of wood
(iv) Hammering of a nail into a piece of wood
Which of the following statement is incorrect for a chemical reaction?
The chemical name of baking soda is sodium bicarbonate.
Which is used as a catalyst during the process of hydrogenation of oils?
Write the characteristics of chemical change.
