1.The atomic symbol of silver is _____
A.Si
B.S
C.Au
D.Ag
2.A box contains some identical red colour balls labelled as A each weighing 2 g. Another box contains identical blue colored balls, labelled as B, each weighing 5 g. In the combinations AB, AB2, A2B and A2B3 which is applicable?
A.Law of Definite proportion
B.Law of multiple proportion
C. Law of conservation of mass
D.None of the above
3.What is the value of Avogadro’s number?
A.6.02 x 10^-23
B.6.02 x 10^23
C.6.02 x 10^-22
D.6.02 x 10^22
4.Which of the following is the correct pair of atom and its atomic symbol?
A.Sulphur–Su
B.Potassium–P
C.Phosphorus–P
D.Sodium–S
5.What is the chemical formula of calcium carbonate?
A.CaCO3
B.CaO
C.CaCl2
D.Ca(OH)2
6.How many moles are present in 40 g of He?
A.5 moles
B.20 moles
C.6 moles
D.10 moles