Which of the following group of elements react violently with hydrogen at room temperature?
Correct answer: D. Rb and Cs
- A. Na and K
- B. Li and Na
- C. K and Rb
- D. Rb and Cs
Explanation
Caesium reacts explosively with water, potentially shattering the container, to form caesium hydroxide and hydrogen. Rubidium, being denser than water, also reacts violently, spitting out of the container and forming rubidium hydroxide solution and hydrogen. The other options, while involving alkali metals, do not exhibit the same level of violent reaction with hydrogen at room temperature as rubidium and caesium do.
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About s-Block and p-Block Elements
The s and p blocks are studied through their valence-shell configurations, periodic trends and characteristic chemical properties. Work covers the reactions of Group I and Group II elements, the behaviour of Group IV elements, and how atomic size, ionization energy, electronegativity and metallic character change across periods and down groups.
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