The element that has the fewest valence electrons available for bonding I believe is Hydrogen.
Answer:
54
Barium atomic number is 56, this means that it has 56 protons in its nucleus and put it as a period 6 element. an uncharged barium atom would have 56 electron also. However as a group 2 element barium easily loses 2 electron to form the +2 cation. the ions has 56-2=54
Answer:
Titration
Explanation:
The best technique which can be used to determine the number of moles of the HCl in the sample is titration.
The given amount of HCl solution must be titrated with known concentration of the base like NaOH.
The volume of NaOH required must be noted also.
According to the reaction,
At equivalence point
Moles of 
= Moles of 
Considering:-
Moles of 
Thus, in this way, moles of HCl can be determined.
<u>Given:</u>
Moles of Al = 0.4
Moles of O2 = 0.4
<u>To determine:</u>
Moles of Al2O3 produced
<u>Explanation:</u>
4Al + 3O2 → 2Al2O3
Based on the reaction stoichiometry:
4 moles of Al produces 2 moles of Al2O3
Therefore, 0.4 moles of Al will produce:
0.4 moles Al * 2 moles Al2O3/4 moles Al = 0.2 moles Al2O3
Similarly;
3 moles O2 produces 2 moles Al2O3
0.4 moles of O2 will yield: 0.4 *2/3 = 0.267 moles
Thus Al will be the limiting reactant.
Ans: Maximum moles of Al2O3 = 0.2 moles
The frequency of a photon of red light with wavelength 4.50 x 10−7m is 6.67 x 1014Hz
