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प्रश्न
Name the following:
The products obtained during ‘photosynthesis’ – which is a chemical change.
उत्तर
Glucose and Oxygen.
APPEARS IN
संबंधित प्रश्न
Complete and balance the following chemical equations
NaCI + `AgNO_3` `→`
Complete and balance the following chemical equations:
\[\ce{Pb(NO3)2->[heat]}\] _________
What are oxides ?
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Reduction is a chemical reaction in which there is
- removal of hydrogen
- removal of oxygen
- addition of oxygen
- none of these
FILL IN THE BLANK
In a double decomposition precipitation reaction both the reactants must be ............ soluble.
FILL IN THE BLANK
Positively charged ions are called ........
Is kerosene an electrolyte or a non-electrolyte ?
Explain the type of reactions on the basis of the direction of reaction.
Write true or false :
Hydrogen sulphide has rotten egg smell .
What is the reaction called when oxidation and reduction take place simultaneously? Explain with one example.
Explain by writing a word equation.
Bubbles are seen on adding lemon juice to baking soda.
Show with the help of diagram of electronic configuration how the following compound is formed from the constituent atoms.
Potassium fluoride
Give an example of a reaction where the following are involved
Heat
When hydrogen burns in oxygen, water is formed; when electricity is passed through water, hydrogen and oxygen are given out. Name the type of chemical change involved in the two cases.
Multiple choice:
Thermal decomposition of sodium carbonate will produce
What do you observe when H2S is passed through a lead nitrate solution.
Distinguish by heating the following in dry test tubs.
Zinc nitrate and copper nitrate.
Write your observation and a balanced equation in the case of the following substances being heated.
Copper nitrate.
Select the correct answer for the following options:
The pale blue precipitated obtained when copper [II] sulphate reacts with sodium hydroxide.
Name the following:
The type of change physical or chemical involved – ‘during respiration in human beings’.
Give a suitable example with an equation to show the representation of a chemical reaction.
Higher order Thinking question
A very hot glass on putting in cold water cracks. What does this change indicate?
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?
Arrange the following statements in correct sequence:
- One side is water-loving and other water-hating molecules.
- When you agitate the cloth, the dirt is surrounded by many molecules and taken away from the cloth.
- The dirt surrounded by the detergent molecules floats in the water making it dirty.
- Finally, the cloth is clean.
- The detergent molecules have two sides.
- Water hating goes and joins with dirt and oil in the cloth while the water-loving joins with the water molecules.
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.
Write a word equation for the chemical change, if any.
Write five changes in the characteristics of a substance that can take place during a chemical change.
Assertion (A): Cutting paper into very small pieces is an irreversible change.
Reason (R): Physical changes are always reversible.
______ is the chemical name of slaked lime.
Acid rain is a result of ______.
