Exercise 1

Question 6 :

The oldest rocks in the earth's crust were once molten, and came from deep inside the earth. The molten rock, called magma, spewed out in volcanic eruptions during the earth;s early life and solidified into hard rock's called


A). granite
B). basalt
C). igneous rocks
D). sedimentary rocks
Answer : Option C

Question 7 :

The law which states that the amount of gas dissolved in a liquid is proportional to its partial pressure is


A). Dalton's law
B). Gay Lussac's law
C). Henry's law
D). Raoult's law
Answer : Option C

Question 8 :

The gas present in the stratosphere which filters out some of the sun's ultraviolet light and provides an effective shield against radiation damage to living things is


A). helium
B). ozone
C). oxygen
D). methane
Answer : Option B

Question 9 :

The most commonly used bleaching agent is


A). alcohol
B). carbon dioxide
C). chlorine
D). sodium chlorine
Answer : Option C

Question 10 :

The nucleus of a hydrogen atom consists of


A). 1 proton only
B). 1 proton + 2 neutron
C). 1 neutron only
D). 1 electron only
Answer : Option A