Answer: false
Explanation: Sodium reacts vigorously with cold water forming sodium hydroxide (NaOH) and hydrogen (H2). The reaction of sodium metal with water is highly heat producing due to which the hydrogen gas formed during the reaction catches fire and burns causing little explosions.
Magnesium metal does not react explosively with water…. Unlike the LOWER Group 2 metals, i.e. calcium, strontium, etc., the reaction of magnesium with water is rather sluggish… formation of magnesium oxide passivates (as it is called) the surface of the metal and prevents rapid oxidation…