Page 7 - Modul A+ Kimia Tg 4_Pan Asia Publications

Uji Kendiri 3.1

1. Tentukan jisim molekul relatif, JMR bagi bahan yang berikut. TP 3
Determine the relative molecular mass, RMM of the following substances.
[JAR/ RAM: H = 1; Cl = 35.5; O = 16; C = 12]

Bahan Sebatian Jisim molekul relatif, JMR
Substance Compound Relative molecular mass, RMM
Gas hidrogen klorida
Hydrogen chloride gas HCl 1 + 35.5 = 36.5
Gas karbon dioksida
Carbon dioxide gas CO 2 12 + (2  16) = 44
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Air
Water H O (2  1) + 16 = 18
2
2. Tentukan jisim formula relatif, JFR bagi bahan yang berikut. TP 3
Determine the relative formula mass, RFM of the following substances.
[JAR/ RAM: Na = 23; Cl = 35.5; Cu = 64; N = 14; O = 16; C = 12; S = 32; Fe = 56]

Bahan Sebatian ion Jisim formula relatif, JFR
Substance Ionic compound Relative formula mass, RFM

Natrium klorida NaCl 23 + 35.5 = 58.5
Sodium chloride

Kuprum(II) nitrat Cu(NO ) 64 + 2[14 + (3 x 16)] = 188
Copper(II) nitrate 3 2

Natrium karbonat Na CO 2(23) + 12 + 3(16) = 106
Sodium carbonate 2 3

Kuprum(II) sulfat terhidrat CuSO .5H O 64 + 32 + 4(16) + 5(18) = 250
Hydrated copper(II) sulphate 4 2

Ferum(II) sulfat heptahidrat FeSO .7H O 56 + 32 + 4(16) + 7(18) = 278
Iron(II) sulphate heptahydrate 4 2

3.2 Konsep Mol
Mole Concept

1. Dalam kehidupan seharian, satu ‘dozen’ telur = 12 biji telur. Namun, dalam bidang kimia, satu ‘mol’ telur =
6.02  10 atau 602 000 000 000 000 000 000 000 biji telur.
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In our daily life, a ‘dozen’ of eggs = 12 eggs. However, in chemistry field, one ‘mole’ of eggs = 6.02  10 or
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602 000 000 000 000 000 000 000 eggs.
2. Unit mol digunakan dalam penyukatan kuantiti bahan. Satu mol bahan mengandungi 6.02214076  10 entiti
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asas bahan tersebut.
The mole unit is used in measuring the quantity of substance. One mole of substance contains 6.02214076  10 elementary
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entities of the substance.
3. Pemalar Avogadro, N ditakrif sebagai bilangan zarah yang terkandung di dalam satu mol bahan
A
itu, iaitu 6.02  10 mol . Sama ada bahan merupakan bahan atom, bahan molekul atau bahan ion.
–1
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number of particles one mole
Avogadro constant, N is defined as the in of a substance, that is 6.02  10 mol .
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–1
A
4. Sama ada bahan atom, bahan molekul atau bahan ion, bilangan zarah di dalam satu mol bahan adalah sama.
Whether it’s an atomic substance, a molecular substance or an ionic substance, the number of particles in one mole of substance
is the same.

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