Question

calcium oxide of 126gm , find no of oxygen atoms

Answer 1

Answer:

(Atomic Mass of Ca=40 u, C=12 u, O=16

agar options ha to option c ha

Correct option is

C

1.806×10

21

Moles of CaCO

3

=

10

3

×100

100

=1 millimoles

Number of oxygen atoms in CaCO

3

=3

Total number of oxygen atoms in 1 milimoles CaCO

3

=10

−3

×3×6.02×10

23

=1.806×10

21

Answer 2

6.022 × 10²³

Explanation:

126 g of CaO has 1 mole of Oxygen

1 mole = 6.022 × 10²³

∴ Number of oxygen atoms = number of oxygen present in CaO × 1 mol

                                             = 1 ×  6.022 × 10²³

∴ 126 g CaO will contain  6.022 × 10²³ of Oxygen atoms.