DAILY EXAMINATION 1 SEMESTER 1 2010/2011
Subject : CHEMISTRY
Class : 10
Do the following problems carefully !
- Determine the number of protons, electrons and neutrons in the following neutral atom and ions : a. Cs b. Mg2+ c. Br-
- What is the difference of isotope, isobar and isoton? Explain with each examples of elements !
- Determine the atomic number, valence electron, group number and period number from the electron configurations given below : A (2 8 3), B (2 8 8 1) and C (2 7) !
- Explain the Thompson’s atomic theory with it’s models !
- Copper occurs in nature as isotopes 63Cu and 65Cu. What percentage of each isotope must be present if the relative atomic mass for Copper is 63.55 ?