Page 8 - Modul A+ Kimia Tg 4_Pan Asia Publications

(a) Bahan atom/ Atomic substance (b) Bahan molekul/ Molecular substance (c) Bahan ion/ Ionic substance

Kuprum/ Copper, Cu
Air/ Water, H O Kalium klorida/ Potassium chloride, KCl
2
1 mol bahan atom, Cu = 6.02  10
23
atom kuprum 1 mol bahan molekul, H O = 6.02  10 1 mol bahan ion, KCl = 6.02  10
23
23
2
1 mol of atomic substance, Cu molekul air unit formula KCl 23
atoms 1 mol of molecular substance, H O 1 mol of ionic substance, KCl = 6.02  10
= 6.02  10 copper 2 formula units of KCl
23
= 6.02  10 water molecules
23
©PAN ASIA PUBLICATIONS
A Bilangan Mol dan Bilangan Zarah
Number of Moles and Number of Particles
1. Rajah 3.3 menunjukkan hubung kait antara bilangan mol dan bilangan zarah dengan menggunakan pemalar
Avogadro, N sebagai faktor penukaran.
A
Diagram 3.3 shows the relationship between the number of moles and the number of particles by using Avogadro constants, N
A
as the conversion factor.
 N
A
Bilangan mol/ Number of moles, n
Bilangan mol, n Bilangan zarah/ Number of particles: Bilangan zarah/ Number of particles
Number of moles, n Atom // Molekul/Molecule // Ion = N
A
 N
A
Rajah/Diagram 3.3

Contoh/Example 6 TP 3
Hitung bilangan atom bagi yang berikut/ Calculate the number of atoms of the following:
(a) 0.2 mol ferum/ iron, Fe
(b) 0.1 mol magnesium/ magnesium, Mg
[Pemalar Avogadro/ Avogadro constant, N = 6.02  10 mol ]
–1
23
A
Penyelesaian/Solution :
(a) Bilangan atom/ Number of atoms (b) Bilangan atom/ Number of atoms
= Bilangan mol  N / Number of moles  N A = Bilangan mol  N / Number of moles  N A
A
A
= 0.2  6.02  10 23 = 0.1  6.02  10 23
= 1.204  10 atom/ atoms = 6.02  10 atom/ atoms
23
22
Contoh/Example 7 TP 3
Hitung bilangan molekul bagi yang berikut/ Calculate the number of molecules of the following:
(a) 3 mol gas nitrogen/ nitrogen gas, N 2
(b) 0.25 mol molekul sulfur/ sulphur molecule, S 8
[Pemalar Avogadro/ Avogadro constant, N = 6.02  10 mol ]
–1
23
A
Penyelesaian/Solution :
(a) Bilangan molekul/ Number of molecules (b) Bilangan molekul/ Number of molecules
= Bilangan mol  N / Number of moles  N A = Bilangan mol  N / Number of moles  N A
A
A
= 3  6.02  10 23 = 0.25  6.02  10 23
= 1.806  10 molekul/ molecules = 1.505  10 molekul/ molecules
23
24

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