Answer : The formula of the gas produced is, 
(phosphine gas)
Explanation :
According to the question, when sodium phosphide is treated with water then it react to give phosphine gas and sodium hydroxide.
The balanced chemical reaction will be:
By Stoichiometry of the reaction we can say that:
1 mole of sodium phosphide reacts with 3 moles of water to give 1 mole of phosphine gas and 3 moles of sodium hydroxide.
Thus, the formula of the gas produced is, (phosphine gas)
Answer:
2 groups
Explanation:
The molecule 3, 3-diethylpentane has 2 ethyl groups because the prefix di- means that there are 2 homogeneous substituent groups present in the molecule.
I do not have my reference table out to see the periodic table but in order to achieve the answer pull out the periodic table. You now know that this element is going to be a metal because it is a good conductor of electric and is malleable. Next you will find both cesium and radon and look in between them to see which one is a metal that has an atomic number that lies between both radon and cesium
