Answer:
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First, we must know what happens in the precipitation reaction. This type of reaction is a double replacement reactions. It is consists of two reactant compounds which interchange cations and anions to form two products. One of the products is an insoluble solid called a precipitate. For the precipitation of CaCO₃, there are two consecutive reactions involved:
1. Slaking of quicklime, CaO
CaO + H₂O ⇒ Ca(OH)₂
2. Precipitation
Ca(OH)₂ + CO₂ ⇒ CaCO₃ + H₂O
The ions that make up the H₂O molecule are H⁺ and OH⁻. According to solubility rules, the cation (positively charged ion) is likely to be attracted to an anion (negatively charged ion). Together, they form an ionic bond. This type of bond is when there is a complete transfer of electrons between the two. The Ca²⁺ cation lacks 2 electrons, while the anion OH⁻ has an excess 1 electron. In order to be stable, 1 Ca²⁺ ion and 2 OH⁻ ions must combine.
Therefore, the answer is OH⁻ ion.
Answer:
Number of valence electrons
Explanation:
Option A
The price elasticity of demand measures buyers’ responsiveness to a change in the price of a good.
<u>Explanation:</u>
Price elasticity of demand holds the responsiveness of need subsequent a variation in a product's cost. In different terms, it’s a process to comprehend out the responsiveness of buyers to inconstancies in cost. Price elasticity estimates the responsiveness of the measure necessitated or outfitted of a good to a shift in its demand.
The price elasticity of demand is the rate fluctuation in the amount demanded of a good or assistance distributed by the percentage shift in the price. Considering the quantity demanded habitually declines with value, the price elasticity coefficient is essentially forever negative.
