1.Notation of sulfur is S. Its mean that in this atom there are ….
a.16 protons, 14 electrons and 14 neutrons
b.14 protons, 16 electrons and 30 neutrons
c.30 protons, 30 electrons and 16 neutrons
d.16 protons, 16 electrons and 14 neutrons
e.16 protons, 16 electrons and 30 neutrons
2.Notation of an element is X; if this atom forms X3+ ion, so there are ....
a.76 electrons around nucleus
b.76 protons inside nucleus
c.79 electrons around nucleus
d.79 neutrons inside nucleus
e.82 protons inside nucleus
3.Known : 8P15; 7Q15; 6R14; and 7S14. A pair of atoms which isotopes one another are ….
a.P and Q
b.R and S
c.P and R
d.Q and S
e.P and S
4.Number of shells of 17A element is ….
5.Electronic configuration of X2+ is 2, 8, 8. Atomic number of X is ….
6.Electronic configuration of X2- is 2, 8, 8. Atomic number of X is ….
7.If X has valence electrons 7 in N shell, atomic number of X is ….
8.Electronic configuration of A is 2, 8, 8, 2, so that ….
a.atomic number of A = 10
b.mass number of A = 20
c.A2+ ion has 20 electrons
d.atomic number of A = 20
e.atomic number and mass number of A = 20
9.An atom has 3 shells, 5 valence electrons, and 16 neutrons. Atomic number and mass number of this atom is ….
a.15 and 16
b.13 and 31
c.15 and 31
d.31 and 13
e.16 and 15
10.The wrong electronic configuration of an atom is ….
a.2e, 8e, 5e
b.2e, 8e, 8e
c.2e, 8e, 6e
d.2e, 8e, 9e
e.2e, 8e, 7e
11.Aluminium has 13 electrons. Electronic configuration of Al3+ ion is ….
b.2e, 8e, 3e
c.2e, 8e, 1e
d.2e, 8e, 6e
e.2e, 8e, 2e
12.Boron has two isotopes. The abundance of the first is 20%. The possible average of atomic mass relative is ….