i guess its e) Mn (VII)
if it was wrong pls let me knw
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.
Answer:
Electrons conducted heat
Explanation:
Iron is a metallic compound. One property of metallic compounds are that they have many loose electrons.
Consider the two rods to be a singular rod, since they touch:
An uncountable number of electrons at one end of the rod are heated, so they gain kinetic energy. Those electrons then collide with other electrons, which energize those as well (although less), which is equal to adding heat. This is a pattern that will flow all the way through the rod.
Answer:

Explanation:
Given

Required
Convert to meters per minutes

Start by converting the speed from miles to meters

So, we have:


Next, we convert time from hours to minutes

So, we have:


<em>Hence, the equivalent of 25 miles per hour is 670.56 meters per minutes</em>
Answer: Oxygen usually forms two covalent bonds or a covalent double bond.
Explanation:
A covalent bond is formed by the sharing of 2 electrons, 1 electron from each of the atoms sharing their electrons.
The number of bonds that each element can form depends on the number of valence (outermost) electrons it contains. Oxygen has 6 electrons in its valence shell and needs 2 more electrons thereby forming a double bond.