كيمياء لغات 2025, للصف الاول الثانوى 2025 , سؤال وجواب 1440 كيمياء لغات 2025, للصف الاول الثانوى 2025 , سؤال وجواب 1440 كيمياء لغات 2025, للصف الاول الثانوى 2025 , سؤال وجواب 1440 .. .... يامراحب بيكم اعضاء وزوار منتديات رسالة حب اهلا بالطلاب .. ربنا يوفقكم ان شاء الله جمعت ليكم النهاردة مجموعة مواضيع جميلة جدا ان شاء الله تنال اعجابكم وتستفادو معانا لمذيد من المواضيع ادخلو قسم التربية والتعليم منتدى المرحلة الابتدائية - منتدى المرحلة المتوسطة - منتدى المرحلة الثانوية - منتدى التعليم العالى - بحوث علمية دى اقسام التعليمى , هتلاقو فيها كل اللى تبحثو عنه بأذن الله مقالات جاهزة , تقارير جاهزة , اختبارات وحلولها , اسئلة واجوبة , نتائج الامتحانات .. . : - A- Explain each of the following: - 1- Each proton spent part of its life in the form of neutron and vice versa. 2- Hydrolysis is the opposite process of neutralization. B- Complete each of the following: - 1- The angle in water molecule is …………………………… 2- Acids dissolved in water to give ……………ions. 3- Washing soda is used to remove …………………. Question Two: - A- Calculate the actual mass of sodium 11Na23if you know that binding energy is 181.55 m.e.v mass of proton = 1.0073 a.m.u, mass of neutron = 1.0087 a.m.u B- Give reasons for: - 1- Aqueous solution of sodium acetate has an alkaline effect. 2- Water is polar compound. 3- Nucleus considered as a store of mass. Question Three: - A- Write the scientific term for each of the following: - 1- Heating of coal in absence of air to prepare aromatic benzene. 2- The method of preparation sulphuric acid in industry. B- Write the balanced chemical equations for each of the following 1- Magnesium oxide with sulphuric acid. 2- Sodium hydroxide with hydrochloric acid. Question Four: - A- Calculate the energy in calories produce from the conversion of 5 grams. B- What is meant by each of the following: - 1- Avogadro’s number. 2- Saponification. Cairo Governorate First Year Secondary Chemistry Exam. Time : - Two Hours Answer the following question: - Question one: - (A)- Choose the correct answer from the following: - 1- On emission of alpha particle from the nucleus of an atom of radioactive element the atomic number decreased by ………………. a) 1 b) 2 c) 3 d) 4 2- The element that has no neutrons in its nucleus is …………………. a) He24 b) H13 c) H12 d) H11 3- Cracking of longer chain hydrocarbon into shorter carbon chains is called ……………………… a) catalytic b) polymerization c) distillation d) catalytic cracking 4- The reuse of waste materials after purification ………………….. a) pollution b) acid c) recycling d) gas in liquid B)- Give reasons for: - 1- A fusion reaction depends on a nuclear chain reaction. 2- The heat content of material differs from one material to another. Answer two questions only from the following: - Question two: - (A)- Complete the following: - 1- Heat of precipitation is the quantity of heat liberated or taken in, on the complete …………………. of …………………. of substance. 2- The atomic number of alpha particle is …………………… and the mass number is ……………….. 3- From the new fuel resources …………………… and …………………agricultural B)- When one mole of sulphuric acid is added to a quantity of water then diluted to 1000 cm 3, the temperature rises by 17 0c. Calculate the amount of heat liberated to the water. Question three: - A)- What is meant by: - 1- Octane number. 2- The chemical formula. B)- What are the damages caused by the pollution of air by carbon oxides? C)- How many molecules are present in 32 grams of sulphur dioxide SO2 ? (S=32 , O=16) Question four: - A)- Explain what happens for each of the following (write the balanced symbolic equations: - 1- Li37 is bombarded with proton projectile. 2- Potassium hydroxide is added to sulphuric acid. 3- U92238 loses alpha particle. B)- 12 grams of radioactive material is kept in a certain place and after 50 days the remaining mass of this radioactive material is 0.75 grams calculate the half life of this radioactive material. Good Luck