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प्रश्न
Name: A greenish-yellow gas.
उत्तर
Chlorine
APPEARS IN
संबंधित प्रश्न
Fill in the blank.
The formation of gas bubbles in a liquid during a reaction is called ......................
TRUE \ FALSE
Weak electrolytes dissociate partially in their aqueous or fused state.
Explain the type of reactions on the basis of the direction of reaction.
Write true or false :
No new substance is formed during a chemical reaction.
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)
Chlorine (Cl2) molecule is formed by ______ of electrons between two chlorine atoms.
Give an example of a reaction where the following are involved
Heat
Define Photochemical reaction
Give an example
Complete and balance the following reaction:
NaCl(aq) + AgNO3(aq) →
Name the gases which Turn moist red litmus blue.
Complete the following table and write your observations.
|
Hydrogen sulphide |
Ammonia |
Sulphur dioxide |
Hydrogen chloride |
|
|
Shake the gas with red litmus solution |
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Shake the gas with blue litmus solution |
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Apply a burning splint to a gas |
Name: A brown gas
What do you observe when dilute sulphuric acid is added to the following:
Sodium Sulphide
Give a word equation for the following reaction.
An exothermic reaction where both the reactants are gases, one of which is oxygen.
A chemical reaction is often accompanied by external indications or characteristics which include –
- Colour change
- Effervescence or gas evolved
- Evolution or absorption of heat
- Formation of a precipitate.
With reference to each of the above indications, state the external indication seen during – Thermal decomposition of mercury [II] oxide.
Explain the term chemical reaction with special reference to reactants and products.
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 a chemical substance which alters the speed of a chemical reaction.
A bag of cement lying in the open gets wet due to rain during the night. The next day the sun shines brightly. Do you think the changes, which have occurred in the cement, could be reversed?
Two chemical species X and Y combine together to form a product P which contains both X and Y
\[\ce{X + Y -> P}\]
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following concerning the species X, Y and P are correct?
(i) P is a compound
(ii) X and Y are compounds
(iii) X and Y are elements
(iv) P has a fixed composition
