Question

Answer the following question:

1. Which electrons in the Selenium (Se) atom shell most notably influence its chemical properties?
2. How many electrons do the fluorine atoms (F), of atomic number 9, have in their outermost energy layer or level?
3. What is the maximum number of electrons when n = 2?
4. How many electrons fit in the f orbital?
5. How many orbitals are there in sublevel d?

6. The third period of the Periodic Table is formed by the elements Na, Mg, Al, Si, P, S, Cl and Ar. Which of them has a smaller size?
7. In general, ionization energy increases from left to right through families. However, boron (B) has a lower ionization energy than beryllium (Be), why _________________________.
8. A calcium ion Ca2 + possesses with respect to the calcium atom Ca _______________________.
9. What is the oxidation number of the elements in group 18?
10. An atom with charge -1 has 18 electrons, 18 neutrons, and an atomic mass of 35 amu. How many protons does this atom have?

11. One of Mendeleev's contributions was the law ??
12. The elements F, Cl, Br, I and At Which of them has greater electronegativity?
13. Silver has two isotopes: 10747 Ag (52%) and 10947Ag (48%). Their masses respectively are 106,905 amu and 108,905 amu. What is the average atomic mass of this element?
14. What is the mass number of a xenon isotope if it has an atomic number of 54 and has 77 neutrons? Who was the scientist who discovered the atomic nucleus? Who was the scientist who discovered the electron?
15. What was the Newlands contribution?
16. The element Potassium (K) is a ??? metal
17. How are the elements organized in the Periodic Table?

18. How are the elements classified in the Periodic Table?

Answer 1

1. Valance electrons (outer most electrons)

2. 7 electrons

3. maximum electrons = 2n2 = 8

4. 14 electrons

5. 5 Orbtais

6. Chlorine

7. due to penetration effect Be4 = 1s2,2s2 B5 = 1s2,2s2,2p1

8. two unit positive charge and 18 Electrons

9.Zero ( fully filled outer most shell)

10. No.of protones = 17

11. The periodic function of the elements is atomc mass.

12. F due to smaller size

14. mass No.= 54 + 77 = 131, Eenest Rutherford, J J Thomson

15.accordng to newlands when elements are arrenged in order to increasing their atomic mass than every eight elements resemble the properties of first element.

16.yes it is mettal

17.according to increasing their atomic no.

18. Elements are classified as Metals, Non Metals and Metaloids.

Question no. 13 solve in paper sheet which is attached with these answers.

in this question values are wrong. i had solved with correct values.