20 cm3 of 1 M H2SO4 is mixed with 20 cm3 of 1 M NaOH. The resulting solution is?
A. acidic with a molarity of 0.50 M H2SO4
B. acidic with a molarity of 0.25 H2SO4
C. neutral
D. alkaline with a molarity of 0.25 M NaOH
E. alkaline with a molarity of 0.50 M NaOH
See your previous post. Same principle. Post your work if you need further assistance.
I got option A, am I correct?
To determine the resulting solution after mixing the given amounts of H2SO4 and NaOH, we need to consider their reaction and the resulting products.
The balanced equation for the reaction between H2SO4 (sulfuric acid) and NaOH (sodium hydroxide) is:
H2SO4 + 2NaOH -> Na2SO4 + 2H2O
This balanced equation indicates that for every 1 mole of H2SO4, 2 moles of NaOH are required to completely react.
Given that both H2SO4 and NaOH are 1 M (1 mol/L) solutions and we have equal volumes of 20 cm3 (or 20 mL) for each, the moles of H2SO4 and NaOH are the same.
Moles of H2SO4 = Molarity x Volume (in L) = 1 M x 20 cm3 / 1000 cm3/L = 0.02 mol
Moles of NaOH = Molarity x Volume (in L) = 1 M x 20 cm3 / 1000 cm3/L = 0.02 mol
Since the mole ratio between H2SO4 and NaOH is 1:2, we have an excess of NaOH. Therefore, not all of the H2SO4 will react, and there will be some unreacted H2SO4 left in the solution.
This means the resulting solution will be acidic because of the presence of unreacted H2SO4. It will also have a lower concentration of H2SO4 than the initial concentrations because it is diluted by the addition of NaOH.
Now, let's look at the answer choices:
A. acidic with a molarity of 0.50 M H2SO4: This answer is incorrect. The resulting solution will have a lower concentration of H2SO4 than the initial concentration.
B. acidic with a molarity of 0.25 H2SO4: This answer is incorrect. The concentration of H2SO4 will be lower than the initial concentration due to its dilution.
C. neutral: This answer is incorrect. The solution will be acidic, as explained above.
D. alkaline with a molarity of 0.25 M NaOH: This answer is incorrect. While NaOH is in excess, the concentration of NaOH does not change during the reaction.
E. alkaline with a molarity of 0.50 M NaOH: This answer is incorrect. The concentration of NaOH does not change during the reaction.
Therefore, the correct answer is B. The resulting solution will be acidic with a lower concentration of H2SO4.