Physical and Chemical Changes

Question 1

Dilute sulfuric acid + Barium Nitrate (Boiling Tube)

Answer 1

Before: Clear, After: White Precipitate

Question 2

Aqueous Potassium + Aqueous Lead (II) Nitrate (Boiling Tube)

Answer 2

Before: Clear, After: Yellow Precipitate

Question 3

Aqueous Iron (II) Sulfate + Aqueous Sodium Hydroxide (Boiling Tube)

Answer 3

Before: Clear, After: Green Solid formed

Question 4

Copper (II) Carbonate (Heat, Bubbled into Limewater)

Answer 4

Before: Green, After: Black, Limewater: effervescence, white precipitate

Question 5

Sugar (Heated)

Answer 5

Before: White, After: Black

Question 6

Iron nails + Copper (II) Sulfate Solution (Displacement Reaction)

Answer 6

Before: Grey, After: Reddish Brown, Formula: Copper (II) Sulfate + Iron –> Iron (II) Sulfate + Copper

Question 7

Iodine Crystals (Crystallization)

Answer 7

Purple vapor is seen, black solid formed on the inner surface of the inverted tube, sublimation