A is obviously out because it leads to a volume of 125.0 milliliters of the new solution and gives you a lower concentration than you were aiming for.
D is out because you are adding 75 milliliters of the stock solution, so your concentration would be too high. You only need 25.0 milometers of stock solution per 100 milliliters of the new solution.
C is also out because it leads to 50.0 milliliters stock solution per 100 milliliters of the new solution and hence the wrong concentration.
B is by default the correct answer. It also details the correct technique. First you add the stock solution (This you know from your calculations to be 25 milliliters.) then you add the water up to the volume you needed. (Because the calculations only tell you the total volume of water not what you need to add) You also add the water last so you can rinse the neck of the flask to make sure you also get all the stock solution residue into the stock solution.
I would add the final step of stirring, but B is the only answer that can be correct.
The answer is 3.10 because it's still the same amount moles of iron.
D. amu
amu stands for atomic mass unit
Explanation:
Lime is added to lower the acidity of lakes when pH levels go too low.
Acidic environment is harmful to aquatic ecosystems. Acidity causes some minerals, such as phosphorus and calcium, in the water to become unavailable to aquatic organisms like plants and fishes ( This means the water hardness is reduced). The low nutrients cause stress and death in the aquatic environment lowering biodiversity. Applying lime raises the pH to neutral levels and improves the health of the aquatic life in the lake. This also improves economic activities in the lake like fishing.
Learn More:
For more on acidicity of lakes check out;
brainly.com/question/3612253
brainly.com/question/3612253
#LearnWithBrainly
