Sagot :
Answers:
1. The periodic table is composed of 7 rows or periods and 18 major groups or columns. Elements in a group have similar properties particularly those elements in four of the groups: Group 1 - The Alkali Metals; Group 2 - the Alkaline Earth Metals; Group 17 - the Halogens and Group 18 - the Noble Gases.
2. In a Modern Periodic Table the Elements are arranged from left to right and top to bottom in the order of increasing atomic number.
3. Elements in the periodic table are also grouped according to metals, non-metals and metalloids. Metals are lustrous, malleable and ductile. They are good conductors of heat. Metals are found on the left side of the periodic table. Nonmetals have a diverse set of properties. Nonmetals are found on the upper right side of the periodic table. Metalloids or semimetals possess the properties of both the metals and the non-metals. Moreover, the elements along the stair step line are the metalloids.
4. There is an existing definite order of reactivity existing among metals and hydrogen according to their ability to displace one another. This arrangement is called the activity series.
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