Answer:
Ag+
Explanation:
If you imagine as if the problem were double replacement, you would pair the Cl with one of the following ions provided in the choices. As seen on Table F, Ag+ paired with Cl- produces an insoluble compound, hence the precipitate. All the other ions shown in the multiple choice section, when paired with Cl- will produce a soluble compound, as a result NOT a precipitate.
Answer:
B
Explanation:
Because the sharpener is attached to an electrical outlet
2,8,3 because Aluminium has the Atomic Number 13
<u>Answer: </u>The correct statement is X is the effective nuclear charge, and it increases across a period.
<u>Explanation:</u>
We are given that:
X = number of protons − number of core electrons
Effective nuclear charge is defined as the actual nuclear charge (Z = number of protons) minus the screening effect caused by the electrons present between nucleus and valence electrons. These electrons are the core electrons.
The formula used for the calculation of effective nuclear charge given by Slater is:

where,
= effective nuclear charge
Z = atomic number or actual nuclear charge or number of protons
= Screening constant
The effective nuclear charge increases as we go from left to right in a period because nuclear charge increases with no effective increase in screening constant.
Hence, the correct answer is X is the effective nuclear charge, and it increases across a period.
Answer:
A
Explanation:
since Mg has a charge of +2 and ClO3 has a charge of 1-, you need 2 ClO3 to cancel out the +2 since 2 ClO3 ions would have a 2- charge