Question

In potaasium calciun magniseium and sodium which is least reactive with cold water

Answer 1

Magnesium

Metal does however react with steam to give magnesium oxide (MgO) (or magnesium hydroxide.

Mg(OH)2, with excess steam) and hydrogen gas (H2).

Answer 2

Hii its tom85

Magnisium is least reactive then calcium because calcium is vigorously react with air and are above in reactivity series.

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