MEDIUM
7th CBSE
IMPORTANT
Earn 100

What are crystals? How can the crystals of copper sulphate be prepared from its impure sample?

Important Questions on Chemicals and Chemical Changes

MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E

Explain the following observations:

Iron objects turn reddish-brown when exposed to air.

MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E

Explain the following observations: The cut surface of fruits and vegetables turn brown.

MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E
Explain the following observations: The blue colored copper sulphate solution turns sea green on addition of iron filings to it.
MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E
Which gas is evolved in the reaction between baking soda and vinegar? What happens when this gas is passed through the lime water? Write the relevant word equations for these chemical reactions.
EASY
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E
Write word equations of the following: Burning of magnesium in presence of oxygen.
MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E
Write word equations of the following: Rusting of iron.
MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E
Write word equations of the following: Reaction of copper sulphate solution on iron filings.
MEDIUM
7th CBSE
IMPORTANT
Science Horizons>Chapter 4 - Chemicals and Chemical Changes>Exercises>Q E
Why do iron fillings acquire a reddish brown deposit when dropped in copper sulphate solution ?