The correct answer is C : energy level.
As you can see in the image of the periodic table presented below, periods are the horizontal columns of the periodic table.
Elements belonging to the same period have the same electron shell, the same number of orbits filled with electrons.
Elements of the same period have similar chemical and physical characteristics
Among formic acid (HCOOH ) and sulfuric acid (H₂SO₄), formic acid is the weak acid. Acidic strength of any acid is the tendency of that acid to loose proton. Among these two acids formic acid has a pKa value of 3.74 greater than that of sulfuric acid i.e. -10. Remember! Greater the pKa value of acid weaker is that acid and vice versa. Below I have drawn the Ionization of both acids to corresponding conjugate bases and protons. The structures below with charges are drawn in order to explain the reason for strength. As it is seen in charged structure of formic acid, there is one positive charge on carbon next to oxygen carrying proton. The electron density is shifted toward carbon as it is electron deficient and demands more electron hence, attracting electron density from oxygen and making the oxygen hydrogen bond more polar. While, in case of sulfuric acid it is depicted that Sulfur attached to oxygen containing proton has 2+ charge, means more electron deficient as compared to carbon of formic acid, hence, more electron demanding and strongly attracting electrons from oxygen and making the oxygen hydrogen bond very polar and highly ionizable.
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Answer:
Na+Cl- + Ag+no3- ---> Na+No3- + Ag+Cl-
A spectator ion is an ion that exists as a reactant and a product in a chemical equation
Explanation:
When a solution of sodium hydroxide, NaOH, is mixed with hydrochloric acid, HCl, the compounds dissociate into the ions Na+, OH-, H+ and Cl-. The hydrogen and hydroxide ions react to form water, but the sodium and chlorine ions stay in solution unchanged.
When pcl5 solidifies it forms pcl4 cations and pcl6–anions. according to valence bond theory, hybrid orbitals that are used by phosphorus in the pcl4 cations are one orbital of s and three orbital of p as it is sp³hydridised.
<h3>What is sp³ hybridization?</h3>
Hybridization is a process or system which specifies the shape and geometry of any element or molecule with bond angles too.
The pcl4 cation is sp³ hybridized because of the phosphorus behave as a central atom here and the 4 chloride molecules are attached with the p- orbitals to the phosphorus molecule.
Therefore, pcl4 cation is sp³ hybridized.
Learn more about sp³ hybridization, here :
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Answer:
La radiación UV-B es parcialmente absorbida por el ozono y llega a la superficie de la tierra, produciendo daño en la piel. Ello se ve agravado por el agujero de ozono que se produce en los polos del planeta.
Explanation: