Worksheet: Alkali Metals
In this worksheet, we will practice describing the compounds and reactivities of alkali metals and trends in their physical and chemical properties.
Which of the following alkali metals is the most reactive?
In which of the alkali metals is the valence electron closest to the nucleus?
The most stable isotope of the radioactive alkali metal francium has a half-life of only 22 minutes. If a sample of francium were large enough to react visibly with water, would the reaction be more or less vigorous than the reaction between cesium and water?
- ALess vigorous
- BMore vigorous
- CSimilarly vigorous
Which of the following statements is false?
- AAlkali metals have lower boiling points than iron.
- BAlkali metals are softer than iron.
- CAlkali metals are denser than iron.
- DAlkali metals are more reactive than iron.
- EAlkali metals have lower melting points than iron.
Which of the following is not a property of alkali metals?
- AThey react with oxygen to produce oxides, peroxides, and superoxides.
- BThey are otherwise known as group 1 metals.
- CThey have low densities relative to most other metals.
- DThey have two s electrons in their outer shell.
- EThey react with water to produce hydroxides and hydrogen.
What gas is formed when an alkali metal reacts with water?
- ACarbon dioxide
Which of the following alkali metals has the greatest density?
Which of the following alkali metals has the lowest melting point?
Which statement about the elements in group 1 is incorrect?
- ASodium has a higher melting point than potassium.
- BLithium is more reactive than sodium.
- CRubidium is more reactive than potassium.
- DCesium is softer than lithium.
- EPotassium is less dense than rubidium.
Which of the following would you not observe when sodium reacts with water?
- ASodium moves around on the surface of the water.
- BThe sodium takes on a spherical shape.
- CThe sodium melts.
- DSodium fizzes where it touches the water.
- ESodium sinks to the bottom of the container.
Which of the following equations properly describes the reaction between sodium and water?
When lithium reacts with water, fizzing is observed where the lithium sits on the surface of the water, and the reaction is relatively slow. When potassium reacts with water, the potassium immediately ignites and moves violently around on the surface of the water, and the reaction is over quickly.
Which statement best describes why these differences are observed?
- ALithium loses its valence electrons more easily than potassium.
- BLithium is less dense than potassium.
- CPotassium is more flammable than lithium.
- DGroup I metals increase in reactivity as you go down the group.
- EThe potassium atoms have lost an electron and formed positive ions.
Complete the following word equation.
- Ametal hydroxide + hydrogen
- Bmetal hydroxide
- Coxide + hydrogen
- Dsalt + oxygen
- Emetal hydroxide + steam
Freshly cut lithium tarnishes in air in under a minute. With which substance is lithium reacting when it tarnishes?
- BCarbon dioxide
Why are the alkali metals lithium, sodium, and potassium stored under oil?
- AThey oxidize if exposed to air.
- BThey react with nitrogen in the air.
- CThey react with the oil to form a protective coat.
- DThey are sensitive to ultraviolet light, which the oil blocks.
- EThey are unstable if not in contact with oil.