In a Lewis structure, formal charges can be assigned to each atom by treating each bond as if one-half of the electrons are assigned to each atom. ... Resonance occurs in cases where two or more Lewis structures with identical arrangements of atoms but different distributions of electrons can be written.
They are so small that they dont scatter light, Or never settle out
Answer:
Mass = 65.4 g
Explanation:
Given data:
Mass of Al₂O₃ = 25 g
Mass of AlCl₃ = ?
Solution:
Chemical equation:
Al₂O₃ + 6HCl → 2AlCl₃ + 3H₂O
Number of moles of Al₂O₃:
Number of moles = mass/ molar mass
Number of moles = 25 g/ 101.96 g/mol
Number of moles = 0.2452 mol
Now we will compare the moles of Al₂O₃ and AlCl₃.
Al₂O₃ : AlCl₃
1 : 2
0.2452 : 2×0.2452 = 0.4904 mol
Mass of AlCl₃:
Mass = number of moles × molar mass
Mass = 0.4904 mol × 133.34 g/mol
Mass = 65.4 g
Answer:
Explanation:
From the question we were given 0.155 moles of HBr, but Br and H are in ratio 1:1, then there are 0.155 moles of Br- ions.
We were also told that the solution contain NaBr, of 25.9 g. Then it must be converted to moles.
molar mass of NaBr =(22.99g + 79.90 )
= 102.89 g per mol.
the moles of NaBr can be calculated as 25.9 / 102.89
=0.252 moles
But Na and Br are in a ratio 1:1 , then there are 0.252 moles of Br-.
Then to get two Br- mol , we will add the first and second mol of Br- together
= 0.155 + 0.252
=0.407 moles.
The given solution has volume of 250 mL, but we know that there are 1000 ml in a liter, then if we convert to L for unit consistency we have
= 250/1000
= 0.25 L
molarity=0.407 moles/0.25 L
= 1.628 M.
Therefore, Br ion molarity is 1.628 M.