Question

identify each of the following elements: 1. alkaline - earth metal in period 3 2. nonmetal in group 14 (4a) 3. halogen in the same period as phosphorus 4. noble gas in period 4 5. metalloid that is in group 14 (4a) and has fewer protons than argon

Explanation:

Step1: Recall periodic - table layout

Alkaline - earth metals are in group 2. In period 3, the alkaline - earth metal is Magnesium.

Step2: Identify group 14 non - metal

In group 14 (4A), non - metals are Carbon and Silicon. Carbon is the lighter non - metal.

Step3: Locate element in same period as Phosphorus

Phosphorus is in period 3. Halogens are in group 17. In period 3, the halogen is Chlorine.

Step4: Find noble gas in period 4

Noble gases are in group 18. In period 4, the noble gas is Krypton.

Step5: Determine metalloid in group 14 with fewer protons than Argon

In group 14, Germanium and Silicon are metalloids. Argon has 18 protons. Silicon has 14 protons and Germanium has 32 protons. So the metalloid is Silicon.

Answer:

1. Magnesium
2. Carbon
3. Chlorine
4. Krypton
5. Silicon