Answer:
0.43 mol.
Explanation:
- Knowing that the no. of moles can be calculated using the relation:
<em>no. of moles (n) = mass/molar mass</em>
mass of MgCl₂ = 41.0 g & molar mass of MgCl₂ = 95.211 g/mol.
<em>∴ n = mass/molar mass</em> = (41.0 g)/(95.211 g/mol) = <em>0.43 mol.</em>
Answer:
8
Explanation:
The atomic mass of an atom refers to the number of protons in the nucleus of an atom. Hence, an element with 6 valence electron mean that it has 6 electrons in its outermost shell.
The atomic Number of elements with 6 valence electrons cannot necessarily be the same, however, elements with 6 valence electrons belong to group six on the periodic table.
From the options given above, :
Atomic number of 8 :
Configuration : 2, 6
Atomic number of 10 :
Configuration : 2, 8
Atomic number of 12 :
Configuration : 2, 8, 2
Hence, only the element with atomic number of 8 has 6 valence electrons in its outer most shell, hence, the answer.
The answer is B.
<u>Each of the points or vertex represent a carbon atom. Answer choice B is the only choice that has 8. </u>
0.1125 moles
Total mass number of AlCl3 = 27 + (3x35.5) = 133.5
Number of moles equals mass divided by mass number
10:133.5=0.075 ( this is the number of moles of AlCl3)
To get the number of moles of Cl2, look at the coefficient of both AlCl3 and Cl2
0.075x3:2=0.1125 moles
I hope this helps
