Checkpoint 1

Which of the following alkali metals was described as "very difficult to cut"?

• Lithium

• Sodium

• Potassium

• Rubidium

What happens to the appearance of freshly cut alkali metals when exposed to air?

• They become more shiny

• They remain shiny

• They become dull

• They turn green

Which alkali metal is the most reactive with water among lithium, sodium, and potassium?

• Lithium

• Sodium

• Potassium

• All are equally reactive

When lithium, sodium, and potassium are added to water, what common products are formed?

• Oxygen gas and oxides

• Hydrogen gas and hydroxides

• Carbon dioxide and carbonates

• Nitrogen gas and nitrides