Which of the following is not the example of physical change?
a) burning of wood
b) boiling of water
c) melting of wax
d) dissolving sugar
Change in which chemical properties of a substance change and a new
substance is formed are called……..
a) physical change
b) chemical change
c) both a and b
d) none of these
Why does the mass of an iron rod increase on rusting? NTS PST –P-2----2015
a) because rust is hydrated hydrogen
b) because rust is hydrated ferric oxide
c) because rust is hydrated nitrogen
d) none of these
Which of the following is/are the example/s of chemical change?
a) burning, Rusting of iron
b) conversion of milk into curds, digestion of food
c) photosynthesis, respiration
d) all of these
…..is a chemical process in which a substance reacts rapidly with oxygen and gives off heat.
a) evaporation
b) combustion
c) conservation
d) heat ration
The original substance is called the …… and the source of oxygen is called the ……...
a) fuel, oxidizer
b) element, O2
c) mater, oxidizer
d) none of these
