Answer:
The dots were not properly located and arrows are not used in Lewis structures
Explanation:
If we intend to write a Lewis structure for a compound, that lewis structure must consist of only dots. These dots actually show the valence electrons on the outermost shell of the molecule.
We do not involve arrows when writing dot electron structures for compounds. The valence electrons of magnesium ought not to be written together because they are not a lone pair, rather they are two unpaired electrons. The use of an arrow suggests a coordinate covalent bond which is not the case here.
The correct lewis structure for MgCl2 is shown in the image attached to this answer.
The correct answer is d) methane (

)
The other options are elements.
For every meter, the equivalent measurements is 1000 millimeters. Hence in the problem where the number of millimeters is given, we divide the number by 1000 to get the number of meters. The answer here is 0.01123 m.
Use M x V = M' x V'
0.300 x V = 0.100 x 250
V = .......... ml
Answer is: household ammonia has 10 times higher H⁺ concentration.
1) pH(household ammonia) = 11.5.
pH = -log[H⁺], approximately the negative of the base 10 logarithm of the molar concentration of hydrogen ions.
[H⁺] = 10∧(-pH).
[H⁺] = 10∧(-11.5).
[H⁺] = 3.16·10⁻¹² M; concentration of hydrogen ions.
2) pH(household bleach) = 12.5.
[H⁺] = 10∧(-12.5).
[H⁺] = 3.16·10⁻¹³ M.
3) 3.16·10⁻¹² M / 3.16·10⁻¹³ M = 10.