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प्रश्न
Fill in the blank:
The basic conditions necessary for a chemical reaction is _______
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उत्तर
The basic conditions necessary for a chemical reaction is close contact .
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संबंधित प्रश्न
The gas we use in the kitchen is called liquefied petroleum gas (LPG). In the cylinder, it exists as a liquid. When it comes out from the cylinder it becomes a gas (Change − A), then it burns (Change − B). The following statements pertain to these changes. Choose the correct one.
How do the following help in bringing about a chemical change?
heat.
Complete and balance the following chemical equations:
Ba`"CI"_2` + `"H"_2"SO"_4` `→`
(aq.) (aq.)
TRUE \ FALSE
Temperature at which a liquid starts boiling is known as the boiling point of that liquid. True or false ?
What are chemical reactions?
State four conditions necessary for chemical reactions to take place.
Copper carbonate when heated, it turns :
Name the type of chemical reaction shown by the following equation:
Fe + CuSO4 → FeSO4 + Cu
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(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
The white particles of baking soda disappear when put in lemon juice. This means that it is a ______ change.
State the original colour of the following substance and colour of residue obtained after heating.
Copper carbonate
Distinguish by dilute sulphuric acid.
Copper and magnesium?
Distinguish by dilute sulphuric acid.
Sodium sulphide and sodium sulphite?
Explain the term ‘chemical reaction’ with special reference to – ‘reactants’ and ‘products’.
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Complete the statement by filling in the blank with the correct word:
The reddish-brown precipitate obtained during a double decomposition precipitation reaction between an iron salt and alkali is __________.
Mention the various conditions required for a chemical reaction to occur.
Which of the following is/are true when milk changes into curd?
- Its state is changed from liquid to semi solid.
- It changes colour.
- It changes taste.
- The change cannot be reversed.
Choose the correct option from below:
How can we prevent rusting?
