Question | Answer |
TO DRAW OCTAHEDARL | ONE LINE GOING UP AND DOWN, 2 WEDGES AT BOTTOM 2 DOTTED LINES UPWARDS. METAL IONS ARE HYDRATED ... WITH OXYGEN OF SIX WATER MOLECULES DATIVE BONDED TO THE CENTRAL ATOM. THESE IONS ARE OCTAHEDRAL .E.G. [CR(H20)6]3+ AND [MG(H2O)6]2+. |
SUMMARY | WORK OUT THE NUMBER OF LONE AND SIGMA BONDS AROUND CENTRAL ATOMS. GIVES ARRANGEMENT OF ELECTRONS. |
REPULSION OF THE BONDS PAIRS AND LONE PAIRS | REDUCES THE BOND ANGLE. |
POLARITY IN H2 AND CL2 – THE AVERAGE POSITION OF BONDING ELECTRONS IS | HALFWAY BETWEEN THE CENTRES |
BUT IN BONDS OF ATOM OF DOFF ELEMENTS | |
(HF H20) IN HF | THE ELECTRON CLOSER TO F BECAUSE MORE ELECTRONEGATIVE. |
ELECTRONEGATIVE IS THE ABILITY | OF AN ELEMENT TO ATTRACT A PAIR OF ELECTRONS IN A COVALENT BOND AND WITHDRAWN ELECTRON DENSITY. |
IN P TABLE THE ELECTRONEGATIVITY | INCREASE ACROSS PERIOD DECREASES DOWN A GROUP. BUT OXYGEN HAS 2ND HIGHEST ELECTRONEGATIVITY. |
WHEN 2 COVALENTLY BONDED ELEMENT HAVE DIFF ELECTRONEGATIVITIES | ON HAS SLIGHT POS AND NEG, THEY ARE POLAR. |
THE BOND ELECTRONS DRAWN TOWARDS | THE MORE ELECTRONEGATIVE ELEMENT MAKING IT NEGATIVE. |
COVALENT BOND | POLAR 100%, |
IF HIGH DIFFERENCE IN ELECTRONEGATIVITY | THEN IONIC. |
SHAPE AND POLARITY BONDS IN CH3CL AND CCL4 | ARE POLAR. |
THE CH3CL IS POLAR BECAUSE | THE C-CL POLARITY IS NO CANCELLED OUT. |
BUT CCL4 IS NOT POLAR BECAUSE | THE POLARITIES IN EACH C-CL BONDS CANCEL OUT AS SYMMETRICAL. |
IS NH3 POLAR | NO, HAS 3 POLAR BONDS AND A LONE PAIR DO NOT CANCEL SO IS POLAR. |
TRIGONAL PLANAR MOLE SO3, BECL3 ARE | NON POLAR COZ POLARITIES DON’T CANCEL. |
H20 IS V SHAPED (POLAR) | POLARITIES DON’T CANCEL. |
CO2 IS LINEAR & | THE POLARITIES CANCEL. |
TO TEST FOR POLAR CAN USE | WATER FROM BURETTE AND BALLOON WHICH HAS BEEN RUBBED ON WOOL – STATIC ELECTRICITY. |
WILL THE POLAR MOLECULE BE ATTRACO THE BALOON ? WHY? | YES AND BEACAUSE OF STAIC ELECTRICITY |
POLARITY OF A MOLECULE MEASURE BY | THE DIPOLE MOMENT |
FOR A DIATOMIC ELEMENT – E.G HCL IS DEFINED BY | THE DIFFERENCE IN CHARGES X THE DISTANCE BETWEEN THE H & THE CL. FOR A POLYATOMIC ELEMENT MORE COMPLICATED. |
POLARITY SHOWN AS | ARROW WITH PLUS AT ONE END |
THE ARROW POINTS TO | THE NEGATIVE ATOM IN THE BOND. |
7 TYPES OF INTERACTION/INTERMOLECULAR ION BETWEEN | 2 IONS 250 KLMOL-1. |
ATOM –ATOM INTERACTION IN A | COVALENT BOND 400. |
PERMANENT DIPOLE DIPOLE- IS BTWEEN | POLAR MOLECULES 1.5 , |
INSTANTANEOUS INDUCED DIPOLE DIPOLE BETWEEN | ALL TYPES OF MOLECULES 1OKJMOL-1. ALKANES |
HYDROGEN BONDING BETWEEN | HFON.20KJMOL-1. |
ION ION BOND IS A | ELECTROSTATIC ATTRACTION BETWEEN POSITIVE AND NEGATIVE ION, |
IN A ION ION BOND THE STRENGTH IS PROPORTION TO | THE PRODUCT OF IT CHARGES AND IN INVERSELY PROPORTIONALLY TO THE SUM OF THE IONIC RADII. |
ATOMS BONDS ARE BETWEEN | ARE COVALENT BONDS |
COVALENT BONDS IS AN | ATTRACTION OF 2 NUCLEI FOR THE SHARED ELECTRONS IN THE BOND, |
SHORT BONDS ARE STRONGER | THAN LONG BONDS. |
ION ELECTRON BONDS ARE BETWEEN | FORCES IN A METAL , SMALL METAL ION BOND MORE STRONGLY THAN LARGE, |
MORE DELOCALISED ELECTRONS | THE STRONGER THE BOND. |
ION WATER MOLECULES | WATER IS POLAR HAS POS AND NEG., THE NEG OXYGEN IS ATTRACTED T THE POS METAL ION AND H THE HYDROGEN ION ATTRACTED TO THE NEG METAL IONS., |
ONE OF THE LONE PAIRS OF ELECTRONS IN THE OXYGEN FORMS | A DATIVE COVALENT BOND WITH THE EMPTY ORBITAL IN A METAL CATION = HYDRATED ION. |
FORCES BETWEEN COVALENTLY BONDED MOLECULES ARE | INTERMOLECULAR FORCES – PERMANENT DIPOLE DIPOLE , INSTANTANEOUS INDUCES DIPOLE FORCES, HYDROGEN BONDS. |
PERMANENT DIPOLE DIPOLE - MOLECULES WITH PERMANENT DIPOLE CAN | ATTRACT NEIGHBOURING MOLECULES. |
THE DIPOLE LINE UP SO THE POSITIVE END IS NEXT TO THE NEGATIVE END OF ANOTHER MOLECULE. = INTERMOLECULAR FORCES. | |
POSITIVE END IS NEXT TO THE NEGATIVE END OF ANOTHER MOLECULE CALLED | INTERMOLECULAR FORCES |
INSTANTANEOUS INDUCED DIPOLE DIPOLE FORCES DISPERSION /LONDON FORCES. THE ELECTRONS | CONSTANTLY MOVING AROUND ITS CAUSES TEMPORARY DIPOLE. |