ساينس الصف الأول الاعدادي – الفصل الدراسي الاول ساينس اولي اعدادي ترم اول In This part we will study : Substances can be classified according to electric conduction into : A. Good conductors of electricity (substances allow electricity to flow through) Examples: •Metals as iron, silver, copper, aluminum • Some solutions as acidic solutions, alkaline _solutions and some salt solutions. B. Bad conductors of electricity (substances don’t allow electricity to flow through) Examples: •Gases. • Some solid substances as sulphur, phosphorus, wood and plastic. • Some solutions as : – solution of hydrogen chloride in benzene. – sugary solution. Life applications of electric conduction : 1. Electric wires (or cables) are made up of copper or aluminum and covered with a plastic layer. Because both of copper and aluminum are good conductors of electricity, while plastic is a bad conductor of electricity. 2. Electric screwdrivers are made up of steel iron, while their handles are made up of wood or plastic. Because steel iron is a good conductor of electricity, but wood and plastic are bad conductors of electricity. Substances are classified according to thermal conduction into : A. Good conductors of heat B. Bad conductors of heat Chemical properties A. Very active metals : B. Less active metals : C. Inactive metals: لمتابعة مستر احمد الباشا وكل ما يخص الساينس : جروب الفيس بوك http://bit.ly/2Of1mcN صفحة الفيس بوك http://bit.ly/2Gq5xMo بالتوفيق مستر احمد الباشا