Answer:
1. analyze the samples while they are frozen
stuff can react differently when it's colder
hope I could help good luck
Answer:In regards to writing the formula, we know that magnesium has a charge of 1+ and sulfate, SO4, has a charge of 1-. Sulfate is a polyatomic ion so the charge of the whole thing is (SO4)1-. When you combine them you end up with MgSO4 and the "heptahydrate" is seven water molecules.
Explanation:
Fe + 3NaBr → FeBr3 + 3Na
The Na is replaced by the Fe atom.
Hydrogen Peroxide slowly decomposing into water and oxygen increases the entropy of the universe. Any reaction of a system always increases the degree of the orderliness of the universe. Decomposition is one of the best examples of increasing the entropy. This is when substance is broken down further to elements or other compounds.
Answer is: ph value is 3.56.
Chemical reaction 1: H₂CO₃(aq) ⇄ HCO₃⁻(aq) + H⁺(aq); Ka₁ = 4,3·10⁻⁷.
Chemical reaction 2: HCO₃⁻(aq) ⇄ CO₃²⁻(aq) + H⁺(aq); Ka₂ = 5,6·10⁻¹¹.
c(H₂CO₃) = 0,18 M.
[HCO₃⁻] = [H⁺<span>] = x.
</span>[H₂CO₃] = 0,18 M - x.
Ka₁ = [HCO₃⁻] · [H⁺] / [H₂CO₃].
4,3·10⁻⁷ = x² / (0,18 M -x).
Solve quadratic equation: x = [H⁺] =0,000293 M.
pH = -log[H⁺] = -log(0,000293 M).
pH = 3,56; second Ka do not contributes pH value a lot.