Question

1. which of the following elements is an alkali metal? mark only one oval. ca cu fe na 6. which of the following elements is an alkaline earth metal? mark only one oval. mg cu fe na 7. which of the following is a noble gas? mark only one oval. ar n h o2 8. which of the following elements is most similar to chlorine? mark only one oval. h he na f

Explanation:

• Alkali metals are in Group 1 of the periodic table. Sodium (Na) is an alkali metal. Calcium (Ca) is an alkaline - earth metal, copper (Cu) and iron (Fe) are transition metals.
• Alkaline - earth metals are in Group 2 of the periodic table. Magnesium (Mg) is an alkaline - earth metal.
• Noble gases are in Group 18 of the periodic table. Argon (Ar) is a noble gas. Nitrogen (N), hydrogen (H) and oxygen (O₂) are not noble gases.
• Elements in the same group have similar chemical properties. Fluorine (F) is in the same group (Group 17, halogens) as chlorine (Cl), so they are most similar.

Answer:

1. D. Na
2. A. Mg
3. A. Ar
4. D. F