CHAPTER 3: CHEMICAL FORMULAE AND EQUATION

1.Number of moles Bilangan mol

2.Number of moles Bilangan mol

3.Number of moles Bilangan mol

1. 2.

3.1) Given that there is 0.5 moles of chlorine gas. Calculate thea) Number of chlorine molecules.

b) Number of chlorine atoms.

2) Given that there is 4.82 x 1021 hydrogen atoms in hydrogen gas . Calculate thea) Number of moles of hydrogen atoms.

b) Number of moles of hydrogen molecules

3) Given that there is 0.5 moles carbon dioxide gas. Calculate thea) Number of moles of carbon dioxide molecules.

b) Number of oxygen atoms.

4) Given that there is 1.806 x 1024 nitrogen atoms. Calculate thea) Number of moles of nitrogen atoms.

b) Number of moles of nitrogen molecules.

5) Given that there is 2.5 moles of magnesium chloride, MgCl2. Calculate the a) Number of magnesium ion, Mg2+.

b) Total number of ions in MgCl2

6) Calculate the number of moles ofa) 2.8 g of iron,[RAM: Fe,56]

b) 10 g of calcium.[RAM: Ca, 40]

7) Calculate the mass ofa) 3 moles of copper atoms.[RAM: Cu,64]

b) 0.4 moles of water molecules, H2O.[RAM: H,1; O,16]

c) 2.5 moles of magnesium carbonate, MgCO3.[RAM: Mg, 24; C,12; O,16]

8) Calculate the number of moles of the following substances.a) 8 g of copper(II) oxide,CuO[RAM: Cu,:64;O,16]

b) 2.5 g of zinc carbonate, ZnCO3[RAM:Zn,65;C,12;O,16]

9) Calculate the mass of 1.204 x 1021 Copper atoms.[RAM: Cu,64]

10) Calculate the number of calcium atoms in 100 g of calcium. [ RAM: Ca,40]

11) Calculate the number of oxygen atoms in 1.6 g of oxygen gas.[RAM: O,16]

12) Calculate the number of molecules that are present in 0.44g of carbon dioxide,CO2.[RAM:C,12;O,16]

13) Calculate the number of moles of 720cm3 CO2 gas at room condition.[Molar volume : 24dm3mol-1 at room condition]

14) Calculate the number of moles of 560cm3 nitrogen gas at room condition.[Molar volume : 24dm3mol-1 at room condition]

15) Calculate the volume of gas that is occupied by 0.3 mol of oxygen at STP?[Molar volume : 22.4 dm3mol-1 at STP]

16) Calculate the volume of gas that is occupied by 0.125 mol of sulphur dioxide at STP?[Molar volume : 22.4 dm3mol-1 at STP]

Number of moles : Number of atom/ number of molecules/ number of unit(ion)Bilangan mol Number Alvogadro 6.02 X 1023

Bilangan molekul Bilangan Unit

Bilangan atom Bilangan ion

Contoh 1:Hitungkan bilangan molekul oksigen dan seterusnya cari bilangan atom dalam 2 mol gas oksigen.

Contoh 2:Hitungkan bilangan atom dalam bahan berikut(i) 1 mol aluminium(ii) 0.2 mol gas hydrogen(iii) 0.6 mol iodinJAwapan

Contoh 3

Satu balang gas berisi 6.02 X1023 molekul karbon dioksida. Hitungkan bilangana.mol karbon dioksidab.atom karbonc.atom oksigen

Contoh 4 0.4 mol garam kuprum(II) klorida, CuCl2 dilarutkan dalam sebikar air. Hitungkan jumlah bilangan ion-ion yang hadir dalam larutan.

PAST YEAR QUESTIONTEST YOURSELF!!!!SPM 2011What is the number of atoms in 0.5 mol of ammonia gas, NH3Berapakah bilangan atom dalam 0.5 mol gas ammonia,NH3[NA: 6.02 X 1023 mol-1]

SPM 20120.58g flavouring substance is used to improve the taste of a pineapple cake. What is the number of molecules of the flavouring substance.0.58g bahan perisa digunakan untuk memperbaiki rasa sebiji kek nenas. Berapakah bilangan molekul bahan perisa itu?NA: 6.02 X 1023 RMM/JMR: 116g mol-1

SPM 2013What is the number of nitrogen atoms in 40.0g of NH4NO3?Berapakah bilangan atom nitrogen dalam 40.0g NH4NO3?[NA: 6.02 X 1023 RMM/JMR: 80g mol-1

SPM 2008What is the number of moles of copper (II) nitrate in 56.4g of copper (II) nitrate, Cu(NO3)2?Berapakah bilangan mol kuprum (II) nitrat dalam 56.4g kuprum (II) nitrat, Cu(NO3)2?[RAM/JAR: O:16, Cu;64 N;14]

SPM 20133.2g of gas X occupies 1120cm3 at standard temperature and pressure(STP). What is the relative molecular mass of X?3.2g gas X menempati 1120 cm3 pada suhu dan tekanan piawai(STP). Berapakah jisim molekul relative bagi X(Molar volume gas/isipadu molar gas: 22.4 dm3 mol -1SPM 2009The relative molecular mass of M2(SO4)3 is 342. What is the relative molecular mass of element M?Jisim molekul relative bagi M2(SO4)3 ialah 342. Berapakah jisim atom relative bagi unsur M[R.A.M/J.A.R: O=16, S=32]

SPM 2010Element J and element Q have proton number of 12 and 9 respectively. What is the relative formula mass of a compound formed between J and Q?Unsur J dan unsur Q masing-masing mempunyai nombor proton 12 dan 9. Berapakah jisim formula relative bagi sebatian yang terbentuk antara J dan Q[RAM/JAR: J=24, Q= 19]

SPM 2010The electron arrangement of atom U is 2.8.1 and atom V is 2.8.7. What is the molar mass of a compound formed when atom U combine wit atom V?Susunan electron bagi atom U ialah 2.8.1 dan atom V ialah 2.8.7Apakah jisim molar bagi sebatian yang terbentuk apabila atom U bergabung dengan atom V[RAM/JAR: U=23 V=35.5]

SPM 2007A ballon contains 6.02 X1023 of gas particles. What is the number of moles of the gas in the balloon?Sebiji belon mengandungi 6.02X1023 zarah gas.Berapakah bilangan mol gas itu dalam belon tersebut

SPM 2009How many molecules are there in 150 cm3 of carbon dioxide, CO2 at room conditions?Bearapakah bilangan molekul 150 cm3 karbon dioksida, CO2 pada suhu bilik[NA : 6.02 X1023 Molar volume gas: 24 dm3 mol-1

PROBLEM SOLVING INVOLVING CHEMICAL EQUATIONExample 10. 2Mg(s) + O2(g) 2MgO(s)

What is the mass of the oxide formed if 1.2g of magnesium is burnt completely in excess of oxygen? /Berapakah jisim oksida yang terbentuk jika 1.2g magnesium terbakar lengkap dalam oksigen yang berlebihan [Relative atomic mass : Mg,24;O,16]

2. CaCO3(s) + 2HCl(aq) CaCl2(aq) + CO2(g) + H2O(l)

What is the maximum volume of carbon dioxide gas released when 2g of calcium carbonate reacts with excess of hydrochloric acid.Berapakah isipadu maksimum gas karbon dioksida yang dibebaskan apabila 2g kalsium karbonat bertindak balas dengan asid hidroklorik[Relative atomic mass: Ca,40;C,12;O,16;H,1;Cl,35.5][Molar volume : 22.4dm3mol-1 at STP]

3. Cu(s) + 2AgNO3(aq) Cu(NO3)2(aq) + 2Ag(s)What is the mass of copper powder used to produced 48.6g of silver metal.Berapakah jisim serbuk kuprum yang digunakan untuk menghasilkan 48.6g logam argentum[Relative atomic mass : Cu,64;Ag,108;N,14;O,16]

4. C(s) + 2PbO(s) CO2 (g) + 2Pb(s) 5. 2Fe2O3 4Fe + 3O2

6. MgCO3 + 2HCL MgCl2 + CO2 + H2O 7. 2Mg(NO3)2 2MgO + 4NO2 + O2