they are good conductor of heat and electricity. they are bad conductor of heat and electricityexcept graphit which is goodconductor.

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1 , c,kd UMetals they have less than (4) electrons in the outermost energy level They are solids except mercury( Hg) which is liquid. They have metalic luster they are malleable and ductile they are good conductor of heat and electricity. During chemical reaction it gives their outermost electrons to other atom and becomes Upositive ionsu. the number of positive charge equal the number of given electrons UEx U ( Na) UNon-metals they have more than (4) electrons in the outermost energy level They are solids and gas except Bromine ( Br) which is liquid. They have no luster they are not malleable and ductile they are bad conductor of heat and electricityexcept graphit which is goodconductor. During chemical reaction it gains electrons from other atom and becomes UNegative ionsu. UEx U ( Cl) 1 proton = 11 proton=11 Electrons=11 Electron =10 Neutron=12 neutron= 12 In chemical reaction:- Sodium (Na) loses one electron and changes to Na + ( Mg) 7 8 proton = 11 proton=17 Electrons=11 Electron =18 Neutron=12 neutron= 18 In chemical reaction:- Chlorine (Cl) gains one electron and changes to Cl - ( 8 16 O) 2 proton = 12 proton=12 Electrons=12 Electron =10 Neutron=12 neutron= 12 In chemical reaction:- Magnesium (Mg) loses two electron and changes to Mg +2 ( Al) 2 26 proton = 8 proton=8 Electrons=8 Electron =10 Neutron=8 neutron= 8 In chemical reaction:- Oxygen (O) gains two electron and changes to O -2 ( 7 14 N) 3 proton = 13 proton=13 Electrons=13 Electron =10 Neutron=14 neutron= proton = 7 proton=7 Electrons=7 Electron =10 Neutron=7 neutron= 14 1

2 In chemical reaction:- Aluminium (Al) loses two electron and changes to Al +3 In chemical reaction:- Nitrogen (N) gains three electron and changes to N -3 U The ion : - U It is the atom which loses or gains an electron or more in chemical reaction Hydrogen ( 1 1 H) has only one electron in the outermost energy level (K) but it is not from metals,it is gaseus non-metal element. Nobel (inert gases) They don`t react in chemical reaction (union ). Each molecule consists of single atom They don`t positive or negative ions. Ex :- 2 4 He Ne Ar 2 8 no. electrons=2 electrons=10 electrons=18 no. proton=2 proton = 10 Proton =18 no. neutron= 18 neutron=18 neutron= 18 Positive ion Negative ion 1-It is an atom of metallic element that loses electrons in chemical reaction 2- It carries positive charge equal the number of lost electrons 3-The number of electrons is less than number of proton and neutron 4- The number of its energy levels is less that of its atom 1-It is an atom of non-metallic element that gains electrons in chemical reaction 2- It carries negative charge equal the number of gained electrons 3-The number of electrons is more than number of proton and neutron 4- The number of its energy levels is equal that of its atom 2

3 Chemical bond Definition :-it is resulted of electric attraction between positive and negative ion 1- It is formed by loss and gain of electrons 2- It arises between metal and non-metal 3- It is formed between two different atoms 5- it produce compound molecules only UEx: - 11Na Na Cl Cl A strong ionic bond formed because of attraction between positive sodium and negative chlorine forming Sodium chloride (NaCl) Na + + Cl - Na + Cl - Ex:- 12Mg Mg +2 2 It is the bond between non-metals atoms through sharing electrons to complete the outer electron shell 1- It is formed by sharing electrons 2- It arises between two non-metal 3- It is formed between two similar or different atoms 4- It is formed because of sharing of electrons between atoms 5- It produce compound and element U Types of covalent USingle covalent bond :- It is bond arises between non-metal atoms,where each atom share another atom with one electron. Ex:- Hydrogen molecules (H 2 ) + H H H H Water molecules (H 2 O) + + H O H H O H U Double covalent bond :- It is bond arises between non-metal atoms,where each atom share another atom with two electron. Ex:-Oxygen molecules O 2 2 8O O A strong ionic bond formed because of attraction between positive Magnesium and negative oxygen forming Magnesium oxide (MgO) Mg +2 + O -2 Mg +2 O + O O O O U Triple covalent bond :- It is bond arises between non-metal atoms,where each atom share another atom with three electron. Ex:- Nitrogen molecules 7 14 N + N N N N 3

4 The valency:- UExamples The valency of Nobel gases The valency of Atomic group It is the number of electrons that an atom gained, lost or shared in chemical reaction. Sodium ( 11 Na) It loses one electron formed Na + So it is monovalent Chlorine ( 17 Cl) It gains or shares with one electron Cl - So it is monovalent Oxygen ( 8 O) It gains or shares with two electron O -2 So it is Divalent. Magnesium ( 12 Mg) It loses two electron Mg +2 So it is Divalent. Aluminium ( 13 Al) It loses three electrons Al +3 So it is Trivalent. U The valency of metal :- 1- Monovalent metal as Lithium (Li) Potassium (K) Sodium (Na) Silver (Ag) 2- Divalent metal as Calcium (Ca) Magnesium (Mg)-Lead (Pb) Mercury (Hg) 3- Trivalent metals as Aluminum (Al)- Gold (Au) 4- Monovalent & Divalent as copper (Cu) 5- Monovalent & trivalent as iron (Fe) U The valency of non- metal :- 1- Monovalent non-metal as Hydrogen (H)- Chlorine (Cl ) Fluorine (F) Bromine (Br) Iodine (I) 2- Divalent non-metal as Oxygen (O) 3- Trivalent & pentavalent as Nitrogen (N) Phosphorus (P) 4- Tetravalent as carbon 5-tetravalent & hexavalent as Sulphur (S) The valency of nobel gases is zero because their outermost is completely filled with electrons. The atomic group :- It is a set of different atoms joined together behave like one atom in chemical reaction and having special valency. 1-Monovalent atomic group as Hydroxide (OH) - - Bicarbonate (HCO 3 ) - - Nitrate(NO 3 ) - Ammonium (NH 4 ) + 2- Divalent atomic group as Carbonate ( CO 3 ) -2 Sulphate (SO 4 ) Trivalent atomic group as Phosphate ( PO 4 ) -3 4

5 Chemical formula Chemical formula:- It is a formula that represent the number and type of the atoms in the molecules. UHow to write the chemical formula of the following :- The compound The way of writing formula Chemical formula No. of elements No.of atoms 1-Hydrogen chloride HCl Sodium Hydroxide NaOH Calcium Carbonate CaCO = Sodium Carbonate Na 2 CO =6 3 5-Aluminium Sulphate Al 2 (SO 4 ) = Sodium Oxide Na 2 O Magnesium Sulphate MgSO = Calcium Sulphate CaSO = Sodium nitrate NaNO = Aluminium Carbonate Al 2 (CO 3 ) = Carbon dioxide CO Sodium Chloride NaCl Water H 2 O 3 2 5

6 Types of compound 1- Acids 2- Bases 3- Oxides 4- Salts First:- Acids They are substances which dissociate in water producing positive hydrogen ions (H + ) Examples:- Hydrochloric acid (HCl ) & Sulphuric acid (H 2 SO 4 ) & Nitric acid (HNO 3 ) U The properties of acids 1-Their formula begins with Hydrogen join with negative group UexceptU (OH) - Or nonmetal 2- They have sour taste 3- They change the colour of litmus paper to red because of Hydrogen ion (H + ) Second:- Bases They are substances that dissociate in water producing negative Hydroxide ions (OH) - Examples:- Sodium hydroxide (NaOH ) & Potassium hydroxide (KOH) Calcium Hydroxide Ca (OH) U The properties of Bases 1-Their formula ends with (OH) - group. 2- Their solution have a bitter taste and feel slippery 3- They change the colour of litmus paper to blue because of Hydroxide ion (OH) - Third :- Oxides They are compounds results from the combination between Oxygen and metals or non-metals. Metal Oxides They are formed from the combination of Oxygen with metal. Ex :- (1) Sodium oxide Na 2 O (2) Calcium oxide CaO (3) Aluminium Oxide Al 2 O 3 Non-metal oxides They are formed from the combination of Oxygen with metal. Ex :- (1) Carbon dioxide CO 2 (2) Sulphur trioxide SO 3 Fourth :- Salts They are found in earth crust Salts are produced from UPositive ion with negative ionu as Sodium chloride (NaCl)/ Lead bromine (PbBr 2 ) UPositive ion with negative atomic groupu as Sodium nitrate ( NaNO 3 )/ Magnesium Carbonate ( MgCO 3 ). 6

7 UPositive atomic group with negativeu ion as Ammonium Chloride NH 4 Cl / Ammonium bromide NH 4 Br UPositive atomic group with negative atomic groupu Ammonium Carbonate (NH 4 ) 2 CO 3 U Salts are classified in to Dissolved in water ( Soluble) Undissolved in water(insoluble) Sodium Chloride NaCl Potassium Sulphate K 2 SO 4 Calcium nitrate Ca(NO 3 ) Sodium sulphide Na 2 S Silver chloride AgCl Lead bromide PbBr 4 Lead sulphate PbSO 4 Magnesium Carbonate MgCO 3 7

8 UActivity One U Observation :-U Magnesium ribbon burns with glowing producing white powder of new substance. U Conclusion:-U magnesium reacts with oxygen(reactants) to form magnesium oxide(products ) (reactants) (product) 2Mg + O 2 2Mg (white powder) Magnesium Oxygen Magnesium oxide Chemical reaction :-It is breaking the bonds in reactant molecules and forms new bonds in products Chemical equation It is a set of chemical formula or symbols representing reactants and products molecules and it represents the condition. EX:- 2Mg + O 2 2MgO C + O 2 CO 2 Law of constant ratio The mass of reactants = the mass of products If the mass of Mg =24 and the mass of Oxygen =16 calculate the mass of reactant and products in the following equation 2Mg + O 2 2MgO The mass of reactant = (2X24 )+ (2X16)= 48+32= 80 The mass of products =2 (24 +16) = 2X40=80 Types of chemical reaction U Direct combination reactionu :- it is reaction that involves of combination of two substance to form new compound. the direct combination reaction between : a- element & element b- Compound & compound C- Element with compound 8

9 Element &element Ex:- C + O 2 CO 2 S + O 2 SO 2 2Mg + O 2 2Mg 2Na + Cl 2 2NaCl b-compound& compound Ex :- Combination of ammonia gas and hydrochloric acid UObservationU :- White fumes clouds of ammonia chloride NH 4 Cl are formed UConclusionU :- Ammonia gas combines with hydrochloric acid forming ammonia chloride (white fume ) NH 3 + HCl conc. NH 4 Cl Element &compound Chemical reaction in our life U Useful application of chemical reaction :-U through chemical reaction many of compound are used in many industry as medicine, fertilizers, fuel, plastics,.. U Negative effect of chemical reaction :- U Fuel burning:-uit causes environmental pollution due to harmful gasses which increase the temperature as : CO 2 (Carbon dioxide gas) :- acts as greenhouses permit the sun rays to enter the earth and not come back. 9

10 CO (Carbon monoxide gas) which causes headache, Dizziness,Faint and stomach aches which lead to death. U Sulphur Oxides :-U as Sulphur dioxide (SO 2 ) & Sulphur trioxide (SO 3 ) They are acidic gases causes Building corrosion & breathing problem (respiratory system malfunction. U Nitrogen oxide :-U As Nitric oxide (NO) & Nitrogen dioxide (NO 2 ) They are gasses resulting at the time of lighting They are poisonous and affect the nervous tsystem. U Burning of coal and cellulose fibers :- Uas burning of paper & cigarettes causes air pollution 10