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.
Hi uhh i've never really typed in Spanish but here I go! :)
Un ano luz es equivalente a 9.467 PM
Answer:
The Relative Formula Mass of Fe(NO₃)₂ is 179.8524 grams
Explanation:
The Relative Formula Mass is the mass of one mole of a compound expressed in grams, obtained by adding together the Relative Atomic Masses, RAM, of the elements which makes the compound
The Relative Formula Mass of a compound is the same as its Relative Molecular Mass
The relative formula mass of Fe(NO₃)₂ is given as follows;
The relative atomic mass of Fe = 55.845 amu
The relative atomic mass of nitrogen, N = 14.0067 amu
The relative atomic mass of oxygen, O = 15.999 amu
Therefore, we have;
The formula mass of Fe(NO₃)₂ = (55.845 + 2×(14.0067 + 3×15.999)) amu = 179.8524 amu
The Relative Formula Mass of Fe(NO₃)₂ = 179.8524 grams.
The answer is Na-F. The F has highest electronegativity among these elements. So we need to find the element with smallest electronegativity. And this element is Na.