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प्रश्न
Fill in the blank:
During a chemical reaction transfer of ________ takes place.
उत्तर
During a chemical reaction transfer of energy takes place.
APPEARS IN
संबंधित प्रश्न
State whether the following statement is true or false. In case a statement is false, write the corrected statement.
Iron pipes coated with zinc do not get rusted easily.
Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.
\[\ce{NH3_{(g)} + HCl_{(g)} -> NH4Cl_{(s)}}\]
Define catalyst.
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer
Which of the following is a reducing agent?
- oxygen
- chlorine
- hydrogen
- none of these
FILL IN THE BLANK
In a ............ change, new substances are formed.
What are chemical reactions?
How is a strong electrolyte different from a weak electrolyte?
Fill in the blank
A new substance is always formed in a _______ change.
Explain the following reaction with one suitable example of Displacement reaction.
Name the type of chemical reaction shown by the following equation:
NaOH + HCl → NaCl + H2O
Show with the help of diagram of electronic configuration how the following compound is formed from the constituent atoms.
Potassium fluoride
Write the chemical reaction where the following changes are observed.
Gas is evolved
Name: A brown gas
What is observed in performing the following :
| Hydrogen | Oxygen | Carbon dioxide | Chlorine | |
| Litmus test | ||||
| Apply a burning splint to the gas | ||||
| Colour of gas | colourless | colourless | colourless | greenish-yellow |
| Odour of gas |
State the original colour of the following substance and colour of residue obtained after heating.
Ammonium dichromate
State the original colour of the following substance and colour of residue obtained after heating.
Lead nitrate
Write your observation and a balanced equation in the case of the following substances being heated.
Zinc carbonate.
Select the correct answer for the following options:
The pale blue precipitated obtained when copper [II] sulphate reacts with sodium hydroxide.
Give balanced equation for the following conversion affected by heat alone on the substance:
Zinc nitrate to nitrogen dioxide
Select the correct answer from the options given below:
State the gaseous product formed, when
An active metal reacts with dilute sulphuric acid.
Select the correct answer from the options given below:
State the gaseous product formed, when
An ammonium salt reacts with an alkali.
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Ammonium dichromate.
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Zinc carbonate.
When lithium metal is placed in hydrochloric acid, _______ gas is evolved.
The changes in which new substance with new chemical properties are formed are ______.
Give two examples for each of the following cases:
Chemical changes.
______ are substances that speed up the process of a chemical change and it will not undergo any change during the course of the reaction.
Galvanization is a process in which ______ is coated as a layer of iron.
Write the equation for the process of formation of rust.
What is the difference between reactants and products?
