Group I and VII Elements

Which of the following properties would most likely belong to an element in Group I?

• Low density, low melting point, react vigorously with water

• Low density, high melting point, mild reaction with water

• High density, low melting point, react vigorously with water

• High density, high melting point, mild reaction with water

Chlorine is the second element of Group VII in the Periodic Table. Which statement about chlorine is true?

• It forms monatomic molecules.

• It is the least reactive of Group VII elements.

• The compound formed when chlorine reacts with magnesium has the formula MgCl2.

• Chlorine readily gives out one electron to form ionic compound with metal.

Astatine is below iodine in the Periodic Table. Which of the following best describes astatine at room temperature?

• black solid

• black liquid

• reddish-brown solid

• reddish-brown liquid

Which of the following is true about Group VII elements?

• Chlorine is a greenish-yellow liquid.

• Bromine is a reddish brown liquid.

• Iodine forms covalent compound that is soluble in water.

• Astatine forms ionic compound that is soluble in organic solvent.

The bonding present in Group I (alkali metals) elements is ....

The structure present in Group VII (halogens) is ...... ..... structure.

Select all the correct statements.

• Sodium exploded into purple flame in water.

• Potassium reacts explosively in water.

• Sodium reacts less vigorously in water.

• Reaction of potassium changes the water (with Universal Indicator) from green to blue.

How does melting points of Group I and VII elements change going down the group? Explain your answer considering the bonding and structure of the elements.