The water was set to room temperature, and contained phenolphthalein, a chemical compound that turns colourless in acidic solutions and pink in basic solutions. Cesium reacts explosively with cold water, and reacts with ice at temperatures above -116°C. Cesium react with water to produce cesium hydroxide and hydrogen. Cesium also reacts vigorously with acids, the halogens, sulfur, and phosphorus. Cesium hydroxide is a strong base and attacks glass. Cesium, gallium, and mercury are the only three metals that are liquid at or around room temperature. Occurrence in nature The abundance of cesium in the Earth's crust has been estimated at about 1 to 3 parts per million. If caesium is burned in air, the result is mainly formation of orange caesium superoxide, CsO 2. Picture of reaction: Сoding to search: 2 Cs + 2 H2O = 2 CsOH + H2. The caesium sample they used was kept in liquid nitrogen before it was dropped into the water from about a metre above. Cesium reacts with the halogens to form a fluoride, chloride, bromide, and iodide. Taking cesium along with "water pills" might decrease potassium in the body too much. Cs(s) + O 2 (g) → CsO 2 (s) Reaction of caesium with water. Thermodynamic properties of substances The solubility of the substances Periodic table of elements. Our channel. Caesium (cesium in USA) metal reacts rapidly with water to form a colourless solution of caesium hydroxide (CsOH) and hydrogen gas (H 2). Find another reaction. Add / Edited: 03.04.2015 / Cesium reacts with cold water to form hydrogen gas and a solution of cesium ions and hydroxide ions. 2Cs(s) + 2H₂O(l) → H₂(g) + 2Cs⁺(aq) + 2OH⁻(aq) The reaction is so explosive that it often shatters the container. Cesium is “extremely pyrophoric, ignites spontaneously when in contact with air, and explodes violently in water or ice at any temperature above -116 ° C”. Cesium must be stored under kerosene or a mineral oil to protect it from reacting with oxygen and water vapor in the air.