Sec 2 | Chemistry | Mr.Ahmed ElBasha

شرح كيمياء الصف الاول الثانوي لغات - الفصل الدراسي الأول شرح كيمستري اولي ثانوي - ترم أول لينك تحميل الملزمة

لينك تليجرام

In This Lesson :

Chemistry: It is the science that is interested in studying the composition and properties of matter, the changes that occur on it, the reactions of different substances with each other and the suitable conditions for these reactions. Importance of chemistry • The ancient Egyptians used some chemicals in mummification. • Since the ancient civilizations, chemistry has been related to: - Metals and mining. - Medicine. - Some technical industries, such as: • tanning. • dyeing of clothes. • production of glass. • Production of colors. - Nowadays, chemistry has very essential roles in all aspects of life. Branches of Chemistry : The fields of studying chemistry: Studying Understanding Obtaining Treating Studying the atomic and molecular structure of matter (the bonds within it) to identify the properties of matter quantitatively and qualitatively. Understanding and controlling the chemical reactions and their conditions. Obtaining new beneficial products that can be used in medicine, agriculture, engineering and industry. Treating some environmental problems, such as : rust, pollution of (water - air - soil), the shortage of water and energy resources. Chemistry is considered the center of most of other sciences, because it is essential to understand the other sciences. Examples: Biology : is interested in studying the living organisms. Chemistry : is interested in studying the chemical reactions that occur inside the living organisms (e.g. digestion, respiration and photosynthesis) . Physics is interested in : Studying Inventing Trying to understand Studying all about the matter like its movement, energy, mass and velocity. Inventing new more accurate methods for measuring. Trying to understand the natural phenomena and the forces affecting them. Chemistry helps in agriculture by:  Selecting the suitable soil for planting a certain crop by the chemical analysis which determines the ratios of the soil components and the degree of sufficiency of these components for this plant or crop.  Increasing the productivity of crops, as chemistry can prepare the suitable fertilizers for each crop.  Producing the insecticides to get rid of the agricultural pests. Measurement in chemistry Any measuring process must include two main points, which are :  Numerical value: describes the measured quantity or property.  Suitable measuring unit: indicates a certain standard to which the measured quantity is being referred Example : When we say that the length of the football playing field is 100 yd. We mean that the field is 100 times longer than the standard length which is called Yard (yd). The importance of measurement is clearly obvious, as follows :  Giving information about the type and the concentration of elements forming the substance : Nutrition facts labels are very important for the consumer, as it enables him to be aware of the types and the concentrations of the components. Application : Measuring the concentrations of the ions which form the salts in mineral water. * By analyzing the data on the labels of each of the two bottles, the following can be concluded : The consumer who follows low salt diet is preferred to use bottle (A) , where it contains lower amounts of ions forming the salts. • The person who consume 1.5 L of water of bottle (B) during one day, he will receive an amount of calcium ions Ca2+ equals 70 x 1.5 = 105 mg  Monitoring and health protection. Environmental safety and health protection requires monitoring each of the following : 1. The validity of drinking water for human use. 2. The purity of air. 3. Safety of food and agricultural products. بالتوفيق مستر احمد الباشا

شرح مادة الساينس لكل المراحل الدراسية مجانا

مراجعة نهائية للصف الثالث الاعدادي مراجعة نهائية تالتة اعدادي ساينس الفصل الدراسي الثاني لينك تحمل الملزمة

لينك التليجرام

بالتوفيق مستر احمد الباشا