Question

1. what are the rows of the periodic table called?
2. what do they tell us?
3. what are the columns of the periodic table called?
4. what do they tell us?

use the periodic table on the site to answer the following questions.

1. list 3 elements that have similar properties.
2. which element is in group 14, period 3?
3. how many valence electrons does sodium have?

Explanation:

1. In the Periodic Table, rows are called periods.
2. Periods tell us about the number of electron shells an element's atoms have.
3. Columns in the Periodic Table are called groups.
4. Groups tell us about the number of valence electrons (for main - group elements) and similar chemical properties.
5. For example, elements in Group 1 (e.g., Lithium (Li), Sodium (Na), Potassium (K)) have similar properties as they all have 1 valence electron and are highly reactive metals.
6. Silicon (Si) is in group 14 and period 3.
7. Sodium (Na) has 1 valence electron.

Answer:

1. Periods
2. The number of electron shells of an element's atoms
3. Groups
4. The number of valence electrons (for main - group elements) and similar chemical properties
5. Lithium (Li), Sodium (Na), Potassium (K) (or other valid group - based examples)
6. Silicon (Si)
7. 1