تعد التجارب المختبرية من أهم الوسائل التي تمكن من فهم خصائص المواد الكيميائية وسلوكها، كما إنها الوسيلة الوحيدة لتحضير المركبات الكيميائية المختلفة. وقد أدى تطور التكنولوجيا في الوقت الحاضر إلى إستخدام أدوات وأجهزة قياس في المختبر مكنت من زيادة دقة نتائج التجارب وسرعة الحصول عليها. أن تفعيل المختبر وإجراء الأنشطة العملية يمكن أن تحقق عدة أمور منها : 1- تُنمي في الطالب مهارات التفكير العلمي ( الملاحظة ، وتحديد المشكلة، وفرض الفروض، وإختبار الفروض، وإختيار الفرض الصحيح ، الإستنتاج والتعميم ) 2- تنمية القدرة على حل المشكلات والتفكير الإبداعي . 3- تمكن الطالب من تكوين المفاهيم بدلاً من المعرفة المجردة . 4- تساعد الطالب على تكوين الميول والإتجاهات العلمية ونوع الإختصاص في المستقبل . 5- تساعد على ترسيخ المعلومة وبقاء أثر التعلم فترة أطول . 6- تكسب الطالب طرق التعامل مع الأدوات المختبرية والمواد الكيميائية والتعرف على مخاطرها عن قرب وفهم قوانين وقواعد السلامة في المختبر وتطبيقها والمحافظة على سيرالعمل والآلات والأجهزة الموجودة في المختبر. 7- بث روح التعاون بين الطلاب بين المجاميع المختبرية . ويغطي هذا الكتاب مما يحويه من المعلومات الضرورية الوافية لمساقين في الكيمياء اللاعضوية وخاصة في التعرف على الجدول الدوري للعناصر وكل مايحتاجه الطالب في الالمام بالمعلومات التي تفيده من خلال التعرف على المختبرات العملية والتي تخص المرحلة الثانية . ويتميز هذا الكتاب بشموله بالتجارب العملية لثلاثين تجربة والتي تخص حول مركبات عناصر في الجدول الدوري. ويعتبر هذا الكتاب كمدخل في توضيح العلاقة بين المنهج النظري والمنهج العملي بشكل مترابط المفاهيم من خلال تعرف الطالب على التجارب العملية لما لها من مجالات تطبيقية في بيئته. وإشتمل الكتاب على عشرة فصول : الفصل الأول: توجيهات مختبرية وتعليمات عامة - نموذج كتابة التقريرعن التجربة - التعرف على الأدوات والأجهزة المستخدمة في مختبر الكيمياء ، توضيح الطريقة الصحيحة للتعامل مع الأجهزة ، مبادئ السلامة الأمنية ، مخاطر المواد الكيميائية ، بطاقات التعريف ، قواعد السلامة في تخزين وتداول المواد الكيميائية ،الاشارة الى الإسستعمالات الخاطئة والصحيحة بشكل مخططات او صور او رسوم توضيحية وبعض الإسعافات الأولية . الفصل الثاني: معلومات حول الجدول الدوري للعناصر . الفصل الثالث :الهيدروجين وتجربة (1) وتخص الحوامض والقواعد والأملاح . الفصل الرابع- الفصل العاشر : التجارب من (2-30 ) تخص معلومات عن العناصر بزمر مختلفة مع ذكر المخاطر الكيميائية للمواد الكيميائية التي يتم التعامل معها في المختبر. الملاحق (Appendix ) : وتتضمن بعض الأجوبة النموذجية لبعض تجارب الكيمياء اللأعضوية الواردة في الكتاب مع أسماء جميع عناصرالجدول الدوري وبعض خواصها . الإشارات التحذيرية– إشارات المنع - الإشارات الإجبارية --الإشارات الإستدلالية .
The study aimed to identify the reality of the application of cost accounting system in the contracting institutions in Saudi Arabia, and the extent of the reflection of the application of this system on the effectiveness and efficiency of the general performance of these institutions. Where the research community consists of the contracting institutions operating in the Saudi Arabia, and then a suitable random sample was selected from seventy one institutions. The researchers used the historical method to track the previous studies as well as the descriptive approach to conducting the field study. The study data were analyzed by SPSS statistical program.
The results of this study conclude that there is a
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Abstract
Due to the momentum of winning in the streets of the city of Baghdad as a result of the large number of checkpoints so felt researcher to conduct a field visit to find out the main reasons that led to this congestion and to find practical solutions to mitigate wastage winning the arrival time citizen to where you want the least possible time.
This research aims to overcome the difficulties experienced by citizens to reach their places of work and reduce waste at the time of service and waiting time as well as reduce the cost of waiting.
Has emerged study a set of conclusions, including the use of model queue (G / G / C) and the mome
... Show MoreWhen sites of new communication occurs which represents the merit of the development of communication technology which is characterized by the services of ( facebook-twiter-corapora-youtube-mass space-friendster-flicker-willnecked in addition to the direct services for viber-whatsup-telgram-and chat on) play important role in changing the infrastructure of Arabic societies which are consideredas closed and not changeable societies during near period and the significance of this study comes from the importounce of this subject which is considered as anew trend of the age on the field of media and public response and acceptance inspite of what is known about Arabic society-it doesn’t accept change-this occurance is associated with terms
... Show MoreThe present paper is a qualitative descriptive study. It aims to examine the macro-cultural schemata addressing the concept of violence against women in Iraq from a cognitive linguistic point of view. To meet this objective, a number of Iraqi social caricatures have been selected from two popular and active Iraqi caricaturists, Odeh Al-Fahdawi and Nasser Ibrahim. The selection and the analysis of data have been achieved following the validity and reliability procedures and the ethical considerations. To meet this objective, Sharifian’s Model (2011) of Cultural Schemata has been adopted in data analysis. The study has concluded that the macro-cultural schemata regarding the concept of violence in the selected panels reveals that violenc
... Show MoreIbn Khaldun is one of the best Arab Muslims scientists who participated in establishing Arabic Muslims heritage in all different disciplines & directions specially in sociology, neurological & his political theories which showed the development of Arabic philosophy in all scientific disciplines specially his introduction
Meaning letters in Arabic are characterized by the diversity and abundance of their linguistic material, and are also distinguished by their large number and types, to the point that some of them have reached a hundred letters confined to five categories
The Comedy of patterns dramas that gave Representative possibilities of advanced functionality and wide being dependent on the diversity performance piece , which is intended to provoke laughter at the receiver, through the diversity of genres performing between dancing and singing and Albantomaim and other methods that have made them distinct from the species dramas other being enabled Representative in dealing with all roles across mature and adaptation of his tools of physical and vocal , as the comedy discusses the societal issues many have a factor of psychological and behind their platforms as a tool face is not directly give way to vent citizen injustice and disadvantages of humans and these conditions need to techniques of physic
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Abstract
The human mind knew the philosophy and logic in the ancient times, and the history afterwards, while the semiotics concept appeared in the modern time, and became a new knowledge field like the other knowledge fields. It deals, in its different concepts and references, with the processes that lead to and reveals the meaning through what is hidden in addition to what is disclosed. It is the result of human activity in its pragmatic and cognitive dimensions together. The semiotic token concept became a knowledge key to access all the study, research, and investigation fields, due to its ability of description, explanation, and dismantling. The paper is divided into two sections preceded by a the
... Show MoreIn this work, the performance of the receiver in a quantum cryptography system based on BB84 protocol is scaled by calculating the Quantum Bit Error Rate (QBER) of the receiver. To apply this performance test, an optical setup was arranged and a circuit was designed and implemented to calculate the QBER. This electronic circuit is used to calculate the number of counts per second generated by the avalanche photodiodes set in the receiver. The calculated counts per second are used to calculate the QBER for the receiver that gives an indication for the performance of the receiver. Minimum QBER, 6%, was obtained with avalanche photodiode excess voltage equals to 2V and laser diode power of 3.16 nW at avalanche photodiode temperature of -10
... Show MoreAfter the fall of the Iraqi regime in the 9th of April 2003, and after the disintegration of the country, political and party political chaos that had never been witnessed before, has now taken over. In the past 2 years, the American military forces had a primary role in spreading this chaos and disorder by applying a set of wrong measures and policies. This chaos that is still affecting the iraqi people was completely ignored by the USA even 2 years after the occupation, no serious steps have been taken in order to bring back order and security, on the other hand, most of the government institutions and its forces were disintegrated, along with the decision made by Paul Bremer of dismissing all the iraqi journals and the workers of the
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