Question

Find the ratio by mass of the combining elements in the Cu(No3) 2


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Answer 1

Answer:-

16 : 7 : 24

Explanation:-

In Cu(NO₃)₂ [Cupric Nitrate] , three elements are present i.e. Copper, Nitrogen and Oxygen.

• Atomic mass of Copper (Cu) = 64 u

• Atomic mass of Nitrogen (N) = 14 u

• Atomic mass of Oxygen (O) = 16 u

Thus, ratio by mass :-

= Cu : N×2 : O×3×2

= Cu : N×2 : O×6

= 64 : 14×2 : 16×6

= 64 : 28 : 96

= 64/4 : 28/4 : 96/4

= 16 : 7 : 24

Thus, ratio by mass of the combining elements in Cu(NO₃)₂ is 16 : 7 : 24 .

Some Extra Information :-

The atomic masses of some important elements are :-

• Hydrogen [H] = 1 u

• Carbon [C] = 12 u

• Sodium [Na] = 23 u

• Chlorine [Cl] = 35.5 u

• Potassium [K] = 39 u

• Calcium [Ca] = 40 u

Answer 2

Elements in Copper (II) Nitrate:-

[Cupric Nitrate]

1. Cu (1)
2. N (2)
3. O (6)

Atomic mass of Cu = 64 u

Atomic mass of N = 14 u

Atomic mass of O = 16 u

∴ Ratio:-

(64 u) : (14 × 2 u) : (16 × 6 u)

By taking 4 as common,

= 16 : 7 : 24 (answer).

More:-

• Atomic mass is the mass of an atom.
• $1 u ≈ 1.99 × 10^{-24} g$
• Atomic masses of,

1. H = 1 u
2. He = 4 u
3. Li = 7 u
4. C = 12 u
5. N = 14 u
6. O = 16 u
7. Na = 23 u
8. Mg = 24 u
9. S = 32 u
10. C = 40 u
11. Al = 27 u
12. Cl = 35.5 u
13. K = 39 u
14. Zn = 65 u
15. Fe = 56 u
16. P = 31 u
17. U = 238 u