Answer:
[NaOH} = 0.4 M
Explanation:
In a reaction of neutralization, we determine the equivalence point of the titration. In this case, we have a strong base and a strong acid.
(H₂SO₄, is considered strong, but the first deprotonation is weak)
2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
As we have 2 protons in the acid, we need 2 OH⁻ from the base to form 2 molecules of water.
In the equivalence point we know mmoles of base = mmoles of acid
Let's finish the excersise with the formula
25 mL . M NaOH = 28.2 mL . 0.355M
M NaOH = (28.2 mL . 0.355M) / 25 mL → 0.400
The answer is going to be C) because
A)We know that she put all three boxes in the window and let them sat their for a hour
B)We know that the boxes are the same size
C)She used three different materials,and she wants to measure the warmth of each box. To see which one is the warmest
D)She never said anything about mass
Hopes This Helps:)
Answer:
Option (D) freezing point depression
Explanation:
Calcium chloride is added to the roadways after a snowstorm because it reduces the freezing point of the ice. Further more, it has been observed that the calcium chloride also produces enough heat which enhances the melting of the ice as it produces an exothermic reaction.
Answer: 20.775 g S
Explanation: 3.9x10^23 atoms = 0.648 mol
Atomic mass S = 32.08
S in grams = 20.775