Question

background
bohr diagrams are used to illustrate the probable location of electrons in atoms.
the rows on the periodic table are called periods. the columns are called families.
procedure:

1. draw the bohr models for each element around the element’s symbol.
2. arrange the cards so they resemble the periodic table. i will check it in class.

questions: (as you answer the questions about the bohr diagrams, look at the number of electrons
in the outer energy level and the number of energy levels in the atom.)

1. look at the following cards: h, li, na, k.

a) in what way is each bohr diagram similar? _______________________________
b) in what way is each bohr diagram different? ______________________________

1. look at the following cards: be, mg, ca.

a) in what way is each bohr diagram similar? _______________________________
b) in what way is each bohr diagram different? ______________________________

1. look at the following cards: (b, al) (c, si) (n, p) (o, s) (f, cl

a) in what way is the bohr diagram for each pair similar? ______________________
b) in what way is the bohr diagram for each pair different? _____________________

1. in general what can be said about every element in the same family of the periodic table?

_____________________________________________________________________________
5 look at the following cards: he, ne, ar.
a) in what way is each bohr diagram similar? _______________________________
b) in what way is each bohr diagram different? ______________________________

1. look at the following cards: h, he.

a) in what way is each bohr diagram similar? _______________________________
b) in what way is each bohr diagram different? ______________________________

1. look at the following cards: li, be, b, c, n, o, f, ne.

a) in what way is each bohr diagram similar? _______________________________
b) in what way is each bohr diagram different? ______________________________
9 look at the following cards: na, mg, al, si, p, s, cl, ar.
a) in what way is each bohr diagram similar? _______________________________
b) in what way is each bohr diagram different? ______________________________

1. in general what can we say about all elements in the same period of the periodic table?

_____________________________________________________________________________

Explanation:

Question 1

Part (a)

H, Li, Na, K are in Group 1 (alkali metals, plus H). Their Bohr diagrams have 1 electron in the outermost energy level.

These elements are in different periods. H has 1 energy level, Li has 2, Na has 3, K has 4. So the number of energy levels (electron shells) differs.

Be, Mg, Ca are in Group 2 (alkaline earth metals). Their Bohr diagrams have 2 electrons in the outermost energy level.

Answer:

Each has 1 electron in the outer energy level.

Part (b)