Exam 2.doc - Manaret eleman language schools Date:\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026\u2026 science department Prep.3 Model Examination

# Exam 2.doc - Manaret eleman language schools...

This preview shows page 1 - 3 out of 6 pages.

Manaret eleman language schools science department Date:………………………………………………. Prep.3 Model Examination ( 2) Question (1 :( A- Complete the following: ( / 10 ( 1 - Sodium chloride is used in salting and preserve food 2The electric current is the flow of electric charges through a conductor 3 .……………- Nitrates are used in the manufacture of sensitive camera film . 4 - Sodium reacts with water and gives sodium hydroxide and hydrogen Gas evolves . 5 - At the beginning of the reaction the concentration of reactants is 100 % 6-2N 2 O 5 4NO 2 + O 2 7 - The measuring unit of current intensity is ampere but that of the quantity of electricity is coulomb B-What's meant by: 1-Electric current intensity passing through a conductor is 3 amperes The quantity of the electric charges passing through a conductor in one second = 3 coulombs 2-Super saturated solution. It is the solution which allows the dissolution of an additional amount of the solute with the increase in the temperature (the amount of the solute is greater than in the case of saturated solution) 3-Speed of chemical reaction. The change in the concentration of the reactants and resultants at a unit of time. Question (2): ( / 10 ( A- Write the scientific terms : 1
1-A substance whose aqueous solution contains positive protons( Acids ) 2-They are chemical compounds decomposed by heat into element and oxygen gas evolves( Metal oxides ) 3-A chemical compound produced from the reaction of an acid with a base( Salts )

#### You've reached the end of your free preview.

Want to read all 6 pages?

• Fall '18
• mmmm
• Chemistry, sodium nitrate, Sodium hydroxide

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern