Answer:
a) The relationship at equivalence is that 1 mole of phosphoric acid will need three moles of sodium hydroxide.
b) 0.0035 mole
c) 0.166 M
Explanation:
Phosphoric acid is tripotic because it has 3 acidic hydrogen atom surrounding it.
The equation of the reaction is expressed as:
1 mole 3 mole
The relationship at equivalence is that 1 mole of phosphoric acid will need three moles of sodium hydroxide.
b) if 10.00 mL of a phosphoric acid solution required the addition of 17.50 mL of a 0.200 M NaOH(aq) to reach the endpoint; Then the molarity of the solution is calculated as follows
10 ml 17.50 ml
(x) M 0.200 M
Molarity =
= 0.0035 mole
c) What was the molar concentration of phosphoric acid in the original stock solution?
By stoichiometry, converting moles of NaOH to H₃PO₄; we have
=
= 0.00166 mole of H₃PO₄
Using the molarity equation to determine the molar concentration of phosphoric acid in the original stock solution; we have:
Molar Concentration =
Molar Concentration =
Molar Concentration = 0.166 M
∴ the molar concentration of phosphoric acid in the original stock solution = 0.166 M
The answer to this question would be: Because the increase of temperature will increase volume.
Using PV=nRT formula we can see that temperature increase will cause an increase in volume. Overheating will cause the volume increase, then increasing the volume. If the percent value used is based on the volume, it will seem that the water is increased. But if the percent is using mass, there will be no increases.
That is why sometimes scientists using molality in a reaction with high temperature changes.
Answer:
The density is 0,5 g/cm3
Explanation:
The density (δ) is the ratio between the mass and the volume of a compound:
δ=m/v= 3 g/6 cm3= <em>0,5 g/cm3</em>