To find the mole of a substance, you take the mass divided by the molar mass of that substance~
Answer:
The correct answer to the question which statements about Avogadro’s Law is false is
c. At constant T and P, doubling the moles of gas decreases the volume by half.
Explanation:
Avogadro's law describes the relationship between the volume of a mass of gas and the number of moles present. Avogadro's law states that at standard (or the same) temperature and pressure, equal volumes od all gases contain equal number of molecules
That is mathematically
where
V₁ = volume of first sample
V₂ = volume of second sample
n₁ = number of moles in first sample
n₂ = number of moles in second sample
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.
This link might help you!!
https://www.eiu.edu/biology/bio1500/writing_a_lab_report.pdf
The head of the phospholipids molecule is attracted to water, the tail repels water
