Answer: there is none, there is no group six period 2 as far as i know .
Explanation:look up the periodic table
Answer:
B. the atomic weight of the element
Explanation:
since it talks about mass i think weight
Answer: 8.25 moles of oxygen are produced.
Explanation: The reaction follows:

By Stoichiometry,
As, 4 moles of Aluminium is produced by 2 moles of aluminium oxide
11 moles of aluminium will be produced by = 
Now, 2 moles of aluminium oxide produces 3 moles of oxygen, so
5.5 moles of Aluminium oxide will produce = 
Hence, 8.25 moles of oxygen will be produced.
Answer: The molality of solution is 17.6 mole/kg
Explanation:
Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.
where,
n = moles of solute
= weight of solvent in kg
moles of acetone (solute) = 0.241
moles of water (solvent )= (1-0.241) = 0.759
mass of water (solvent )=
Now put all the given values in the formula of molality, we get
Therefore, the molality of solution is 17.6 mole/kg