I believe the answer would be A. Electronegativity increases across a period.
Answer:
The pH of a solution of 0.00278 M of HClO₄ is 2.56
Explanation:
pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance and is calculated as:
pH= - log [H⁺]= - log [H₃O⁺]
On the other hand
, a Strong Acid is that acid that in an aqueous solution dissociates completely. In other words, a strong acid completely dissociates into hydrogen ions and anions in solution.
HClO₄ is a strong acid, so in aqueous solution it will be totally dissociated. Then, the concentration of protons is equal to the initial concentration of acid and the pH will be calculated:
pH= - log 0.00278
pH= 2.56
<u><em>The pH of a solution of 0.00278 M of HClO₄ is 2.56</em></u>
Answer:
0.15M
Explanation:
The equation for molarity is M= n/L. Where "M" is Molarity, "n" is the number of moles of solute, and "L" is the total liters in solution.
You need to calculate the number of moles from the given grams. The molar mass of KOH is (39.098+ 16 +1.008)= 56.106g. To calculate the mols of KOH,
×
= 0.44558... mol, you see that the grams unit cancel out leaving you with mol as the unit.
The volume is given in L already so no need to do any conversion. M=
= 0.1485M ≈ 0.15M
Answer:

Explanation:
Assuming that all caculations are at normal pressure and -1.72°C :

Where
is the number of moles of hydrogen
is the mass of hydrogen
is the density of hydrogen