Answer:
2.28 M
Explanation:
Step 1: Given data
Percent by mass (%m/m): 20.0 %
Density (ρ): 1.114 g/mL
Step 2: Calculate the percent by volume (%m/v)
We will use the following expression.

Step 3: Calculate the moles of solute in 100 mL of solution
The molar mass of phosphoric acid is 97.99 g/mol. The moles corresponding to 22.3 g are:

Step 4: Calculate the molarity of the solution
0.228 moles of solute are in 100 mL (0.100 L) of solution. The molarity of the solution is:

55.49 moles are in one kilogram of water...
The n=2 --> n=1 transition in the hydrogen atom has the shortest wavelength. In addition, microwave has a highest frequency wave. In finding the limiting reagent, grams divided by the molar mass and the answer will be divided by the coefficients and the lowest amount is the limiting reagent.
I'm pretty sure the answer is the first one. The fact that it doesn't have a full valence shell means that electrons from other atoms can react and bond with the sodium atom.
Hope this helps x
Answer:
pH = 1.95
Explanation:
For polyprotic acids, it is generally assumed that all H⁺ comes from the 1st ionization step. The amount of H⁺ delivered into solution for the 2nd and 3rd ionization steps are in the order of 10⁻⁴M and 10⁻⁶M respectively and provide very little change in pH from the quantity delivered in the 1st ionization step.
Therefore... the [H⁺] concentraion and pH are computed as follows...
[H⁺] = √Ka₁[H₃AsO₄] = √(2.5 x 10⁻⁴)(0.500) M = 0.1118M
pH = -log[H⁺] = -log(0.01118) = 1.95