Q1: What elements belong to Group 7 of the periodic table?

A1: The elements in Group 7 are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

Q2: What is the common name for Group 7 elements?

A2: Group 7 elements are commonly known as the halogens.

Q3: What is the trend in reactivity as you go down Group 7?

A3: The reactivity of halogens decreases as you go down Group 7.

Q4: Which halogen is the most reactive?

A4: Fluorine (F) is the most reactive halogen.

Q5: Which halogen is the least reactive?

A5: Astatine (At) is the least reactive halogen, although it is very rare and highly radioactive.

Q6: Which halogen exists as a diatomic gas at room temperature and pressure?

A6: Chlorine (Cl) exists as a diatomic gas at room temperature and pressure.

Q7: Which halogen has the highest boiling point?

A7: Iodine (I) has the highest boiling point among the halogens.

Q8: Which halogen has the lowest melting point?

A8: Fluorine (F) has the lowest melting point among the halogens.

Q9: What happens when a halogen reacts with a metal?

A9: Halogens react with metals to form compounds called metal halides.

Q10: Explain the trend in boiling points of the halogens.

A10: Boiling points of the halogens increase as you go down Group 7. This is due to an increase in the strength of the van der Waals forces between molecules as the size and Mr (molar mass) of the halogens increase.

Q11: What is the color and physical state of chlorine and bromine at room temperature?

A11: Chlorine is a yellow-green gas, while bromine is a reddish-brown liquid at room temperature.

Q12: What is the displacement reaction between halogens and halide ions?

A12: A more reactive halogen can displace a less reactive halogen from a solution of its salt. For example, chlorine can displace bromine from a solution of bromide ions.