Rubidium.
Lithium, sodium, potassium. rubidium, cesium, francium, calcium, strontium, barium and radium all react with varying degree of vigor with water to produce hydrogen gas. Other metals also will but not as vigorously.
This element is calcium. It is the fifth most abundant element in the Earth's crust and makes up more than 3 percent of the crust. It reacts with water and belongs to the 2nd group of the periodic table.
The gas produced is hydrogen gas (H2). The reaction between sodium metal and water is a highly exothermic reaction that liberates hydrogen gas, which in turn reacts explosively with oxygen in the air when ignited by a burning splint.
All metals more reactive than Zn: Al, Mg, Na, Ca, Ba, K, Li
No, calcium (Ca) metal will not dissolve in water on its own. However, when calcium reacts with water, it forms calcium hydroxide and hydrogen gas.
Sodium will, and some others will too.
Some metals in the table do not react with water
It reacts explosively with water
Lithium is the element that produces a red flame when it reacts with water.
Hydrogen is not inert it reacts explosively with Oxygen to create water H2O
there are some alkali metals. It can be sodium or potassium.
water
Sodium
Potassium (K) reacts most rapidly with water.
Sodium reacts violently with water, while sodium chloride (or table salt) dissolves in water.
Most explosives are not elements, they are compounds, however several elements will react explosively under some conditions. Caesium (132 amu) reacts explosively with water, as would Francium (but Francium is so rare that no one has isolated enough to see or weigh) Several heavy radioactive substances can be made to undergo fission, especially plutonium-239)
Magnesium is the element that loses 2 atoms when reacting, reacts slowly with water, and can conduct electricity.