Seawater found to be seeping up through the canyon floor is why
scientists think Grand Canyon was once covered by an ocean.
Grand cayon is located in Arizona, United States and comprises of a lot of
fossil records and rocks which makes it one of the best sites for geological
study.
The Grand cayon was found to be seeping through its floor which made
scientists think it was once covered by an ocean years ago.
Read more about Grand cayon on brainly.com/question/20629780
Answer:
D 17 amu
Explanation:
because all you have to do is add 9+8=17 :)
Answer:
5.7
Explanation:
(C₂H₅)₃NHCl dissociates according to the following equation.
(C₂H₅)₃NHCl ⇒ (C₂H₅)₃NH⁺ + Cl⁻
The molar ratio of (C₂H₅)₃NHCl to (C₂H₅)₃NH⁺ is 1:1. Then, the concentration of (C₂H₅)₃NH⁺ is Ca = 0.166 M.
(C₂H₅)₃NH⁺ is the conjugate acid of (C₂H₅)₃N. Given the Kb of (C₂H₅)₃N, we can calculate Ka for (C₂H₅)₃NH⁺ using the following expression.
Ka × Kb = Kw
Ka = Kw / Kb
Ka = 1.0 × 10⁻¹⁴ / 5.2 × 10⁻⁴
Ka = 1.9 × 10⁻¹¹
(C₂H₅)₃NH⁺ dissociates according to the following equation.
(C₂H₅)₃NH⁺ ⇄ (C₂H₅)₃N + H⁺
We can calculate [H⁺] using the following expression.
[H⁺] = √(Ca × Ka) = √(0.166 × 1.9 × 10⁻¹¹) = 1.8 × 10⁻⁶
The pH is:
pH = -log [H⁺] = -log 1.8 × 10⁻⁶ = 5.7
Answer:
Nitrate from agriculture is now the most common chemical contaminant in the world’s groundwater aquifers. Aquatic ecosystems are affected by agricultural pollution; for example, eutrophication caused by the accumulation of nutrients in lakes and coastal waters impacts biodiversity and fisheries.
<u>Answer:</u> When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.
<u>Explanation:</u>
Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.
According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.
The overall chemical reaction follows:
The intermediate balanced chemical reaction are:
(1)
(2)
The expression for enthalpy of the reaction follows:
Hence, when the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.