Question

A teacher wants to perform a classroom demonstration that illustrates both chemical and physical changes. Which would be the best demonstration that she could use?

A) bending a piece of aluminum
B)breaking a matchstick
C) dissolving sugar in water
D) burning a candle

Answer 1

Burning a candle because the candle gets smaller and causes a chemical change

Answer 2

D) burning a candle

Step-by-step explanation

When burning a candle no new substance is form.

We have both physical and chemical change occuring.

Physical part: Melting of the solid wax and evaporation of the liquid forms the physical change.

Chemical part: burning of the wax vapour forms the chemical change.