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प्रश्न
Select the correct answer for the following options:
The gas obtained when potassium chlorate is heated in the presence of a catalyst.
विकल्प
Hydrogen
Copper [II] oxide
Oxygen
Copper [II] hydroxide
Ammonia
उत्तर
Oxygen
APPEARS IN
संबंधित प्रश्न
How would you show that setting of curd is a chemical change?
Name three biochemical catalysts found in the human body.
Complete and balance the following chemical equations
Na + H2 O →
Write the missing reactants and products and balance the equations.
................+ HCI `→` NaCI + `"H"_2"O"` + .........................
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Which one of the following alters the rate of the chemical reaction without itself undergoing any change?
- temperature and Pressure
- concentration of reactants
- presence of catalyst
- none of these
What are the characteristics of a chemical reaction ? A chemical reaction is characterised by an irreversible change in which a new substance is formed.
Explain the type of reactions on the basis of the direction of reaction.
True or false
New substances are formed in a chemical change.
Choose the correct option from the bracket and explain the statement giving reason.
(Oxidation, displacement, electrolysis, reduction, zinc, copper, double displacement, decomposition)
To prevent rusting, a layer of ______ metal is applied on iron sheets.
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)
An ______ is drawn in between the reactants and products while writing the equation for a 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.
Give an example of a reaction where the following are involved:
Close contact
Define:
Photochemical reaction
Give one example
Name Affects the acidified K2Cr2O7 paper and also turns lime water dirty milky.
Name: A brown gas
Give a chemical test to distinguish between the following gases.
H2 and O2
Write your observation and a balanced equation in the case of the following substances being heated.
Copper nitrate.
Give reason for the following:
Even though rusting is an exothermic reaction, the heat evolved when an iron nail rusts is unnoticeable.
Give reason for the following:
A characteristic change of colour is seen when a piece of iron is added to copper [II] sulphate solution.
Give balanced equation for the following conversion affected by heat alone on the substance:
Ammonium dichromate to nitrogen
Give two examples where a chemical reaction is accompanied by a change in colour of the reactants and products on completion of the reaction.
______ is not a chemical change.
Silver metal can displace hydrogen gas from nitric acid.
Silver articles turning black: ______:: Boiling of H2O: physical change ______.
State whether the following statements are true or false:
When a candle burns, both physical and chemical changes take place.
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.
What changes do you expect?
When magnesium is burnt in the air, a new substance is formed which is ______.
The chemical name of baking soda is sodium bicarbonate.
Both CO2 and H2 gases are ______.
