CHEMICAL BONDING

DEFINITION OF A CHEMICAL BOND A CHEMICAL BOND IS A MUTUAL ATTRACTION BETWEEN THE NUCLEI AND VALENCE ELECTRONS OF DIFFERENT ATOMS- THAT BINDS THE ATOMS TOGETHER

TYPES OF CHEMICAL BONDING WHEN A BOND FORMS, THE VALENCE ELECTRONS OF EACH ATOM, MOVES INTO DIFFERENT POSITIONS-   THE FORMATION OF A BOND MAKES THE ATOMS MORE STABLE.

SINCE WE KNOW THAT METALS LOSE ELECTRONS AND FORM POSITIVE IONS AND NONMENTALS GAIN ELECTRONS AND FORM NEGATIVE IONS THE ATTRACTION BETWEEN THE POSITIVE AND NEGATIVE IONS FORMS AN ELECTRICAL ATTRACTION- CALLED AN IONIC BOND.

ATOMS THAT DO NOT COMPLETELY GAIN OR LOSE THEIR VALENCE ELECTRONS WILL SHARE THEIR VALENCE ELECTRONS. THE SHARING OF A PAIR OF ELECTRONS BY TWO ATOMS IS CALLED A COVALENT BOND.

COVALENT BOND IF THE PAIR OF ELECTRONS ARE SHARED EQUALLY BETWEEN THE TWO ATOMS,  THE BOND IS CONSIDERED TO BE NON-POLAR NON-POLAR BONDS  MEANS THAT THERE IS NO POSITIVE OR NEGATIVE SIDE OF THE BOND.

IONIC BOND OR COVALENT BOND REMEMBER:  ELECTRONEGATIVITY IS THE MEASURE OF AN ATOMS ABILITY TO ATTRACT ELECTRONS. WE CAN DETERMINE THE TYPE OF BOND FORMED BETWEEN TWO ATOMS, BY MEASURING THE DIFFERENCE BETWEEN THE TWO ATOM'S ELECTRONEGATIVITIES.

BOND TYPE DETERMINED BY ELECTRONEGATIVITY DIFFERENCE COMPARE THE ELECTRONEGATIVITY OF CESIUM AND CHLORINE. ELECTRONEGATIVITY OF CESIUM= 0.7 ELECTRONEGATIVITY OF CHLORINE= 3.0 DIFFERENCE BETWEEN HE TWO ATOMS= 2.3                

DIFFERENCE IN ELECTRONEGATIVITY WHEN THE DIFFERENCE OF ELECTRONEGATIVITY IS GREATER THAN 1.7  THE BOND IS CONSIDERED TO BE  IONIC

TYPES OF BONDS: COMPARE THE ELECTRONEGATIVITY DIFFERENCE BETWEEN SULFUR (ELECTRONEGATIVITY= 2.5)        AND HYDROGEN (2.1)       AND CESIUM (0.7)       AND CHLORINE (3.0) 2.5-2.1= 0.4  BOND TYPE= POLAR COVALENT 2.5-0.7= 1.8  BOND TYPE IS IONIC 3.0-2.5= 0.5  BOND TYPE IS POLAR COVALENT

POLARITY DEFINITION OF POLARITY  A PLANE OR LINE WITH A POSITIVE AND NEGATIVE END (OR POLE)                I.E.- A MAGNET

A POLAR COVALENT BOND A COVALENT BOND- SHARED ELECTRONS BETWEEN TWO ATOMS,  WHERE ONE END OF THE BOND IS (+) AND ONE END IS (-) CONSIDER THE BOND BETWEEN SULFUR AND HYDROGEN                       (SULFUR)-----------(HYDROGEN)  WHICH END OF THE BOND IS (+) AND WHICH END IS (-)

POLAR COVALENT BOND SINCE SULFUR HAS AN ELECTRONEGATIVITY VALUE OF 2.5 AND HYDROGEN HAS A VALUE OF 2.1                       SULFUR IS THE NEGATIVE END OF THE BOND AND                HYDROGEN IS THE POSITIVE END OF THE BOND CONSIDER THE BOND BETWEEN SULFUR AND CHLORINE WHICH END IS POSITIVE AND WHICH IS NEGATIVE

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