Answer:
The correct answer is - sulfur.
Explanation:
In the periodic table, there are 18 groups and 7 rows or periods arranged according to their atomic number or electronic configuration. In the question, it is mentioned that the desired element atomic mass is less than the atomic mass of the selenium which is 78.96, and more than oxygen which is 15.99 with 6 electron valence and present in the third row.
As it has 6 valency of electron it must be in the 16 group of the table that comprises the 6 valency and as it is located in the 3rd row it must be sulfur that also has an atomic mass between selenium and oxygen.
Answer : One mole of an ideal gas occupies a volume of 22.4 liters at STP.
Explanation :
As we know that 1 mole of substance occupies 22.4 liter volume of gas at STP conditions.
STP stands for standard temperature and pressure condition.
At STP, pressure is 1 atm and temperature is 273 K.
By using STP conditions, we get the volume of 22.47 liter.
Hnece, the one mole of an ideal gas occupies a volume of 22.4 liters at STP.
Tabulations of chemical elements differing in their organization from the traditional seen periodic system
A mineral is a naturally occurring, inorganic solid with a definite chemical composition and a crystalline structure formed by geological processes. A rock is an aggregate of one or more minerals whereas a rock may also include organic remains and mineraloids.