Which one of the following metals does NOT react with cold water ?

Which one of the following metals does NOT react with cold water ?

Calcium (Ca)
Potassium (K)
Magnesium (Mg)
Sodium (Na)
This question was previously asked in
UPSC NDA-1 – 2019
Magnesium (Mg) does NOT react with cold water.
Alkali metals (like Potassium and Sodium) react vigorously or even explosively with cold water, producing hydrogen gas and their hydroxides. Calcium, an alkaline earth metal, also reacts with cold water, albeit less vigorously than sodium or potassium, forming calcium hydroxide and hydrogen gas. Magnesium, another alkaline earth metal, reacts very slowly with boiling water and reacts readily with steam to form magnesium oxide and hydrogen, but it does not react with cold water.
The reactivity of these metals with water increases down the group for alkali metals (Li < Na < K < Rb < Cs) and generally for alkaline earth metals (Be < Mg < Ca < Sr < Ba), although the trend for alkaline earth metals reacting with cold water starts effectively at Calcium. Beryllium does not react with water or steam.
Exit mobile version