Answered

An element is soft and can be cut easily
with a knife. It is very reactive and cannot
be kept open in the air. It reacts vigorously
with water. This element is most likely to
be:
(a) magnesium
(b) potassium
(c) phosphorus
(d) sodium



Answer :

GinnyAnswer

Final answer:

Potassium is the correct answer choice due to its softness, high reactivity, and vigorous reaction with water.


Explanation:

Potassium is the element described. It is a soft, highly reactive alkali metal that can be cut easily with a knife and reacts vigorously with water. Potassium must be stored under mineral oil to prevent reactions with air or water.


Learn more about Alkali Metals here:

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