<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.
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Answer:
10.6 grams is approximately 0.10 moles. So you would need about 0.10 moles of sulfuric acid. That converts to about 9.80 grams.
Explanation:
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Answer: B. 12.25 W
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Explanation:
1) Force = Weight = 75 x 9.8 = 735 N
2.)Work = Force x Height = 735 x 5 = 3675 J
3.)Power = Work / Time = 3675 / (5 x 60) = 12.25 W
What are organic and inorganic compounds? Organic chemistry is the study of the carbon compounding molecules. Inorganic chemistry, by contrast, is the study of all compounds that do NOT contain carbon compounds.