An element reacts with oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be

The description of an element that reacts with oxygen to give a compound with a high melting point and is also soluble in water suggests that the element is likely a metal.

Metal oxides typically have high melting points and can be soluble in water to form basic or alkaline solutions. The metal reacts with oxygen to form its oxide, which is often a solid compound with a high melting point. When this metal oxide is dissolved in water, it can form a basic or alkaline solution due to the presence of hydroxide ions (OH⁻) in the solution.

Common examples of such metals include sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg). When these metals react with oxygen, they form metal oxides that can be soluble in water and create basic solutions when dissolved.The element is likely to be calcium.