The answer is: II.The endpoint is recorded when the solution is dark red in color rather than light pink.
The endpoint is the point at which the indicator changes colour in a colourimetric titration and that is point when titration must stop.
Phenolphthalein is colorless in acidic solutions and pink in basic solutions. If this indicator change color to dark red, more base is added and endpoint is not accurate.
If the the acid is spilled before titration, that does not make endpoint wrong and molar mass can be calculated.
In this example we can take acetic acid as carboxylic acid; basic salt sodium acetate CH₃COONa is formed from the reaction between weak acid (in this example acetic acid CH₃COOH) and strong base (in this example sodium acetate NaOH).
Balanced chemical reaction of acetic acid and sodium hydroxide:
CH₃COOH(aq) + NaOH(aq) → CH₃COONa(aq) + H₂O(l).
Neutralization is is reaction in which an acid (in this example vinegar or acetic acid CH₃COOH) and a base react quantitatively with each other.
Answer:
Pressure on Surface A > Pressure on Surface B
Explanation:
Pressu
re on Surface B > Pressure on Surface A
1-pentyne consists of a carbon chain of 5 carbons one with a triple bond. 1-octyne is a carbon chain of 8 carbons with a triple bond at some point. It is known that the longer the carbon chain the higher the boiling point since more energy will be required to break the bonds between carbons. Based on this it is predicted that 1-octyne will have a higher boiling point than 1-pentyne.
The answer to this is solved through stochiometry: the answer is this: 0.0833mol
Answer:
Boron
Explanation:
You can find this by looking at the number of protons in Boron, 5.
Then calculate how many electrons you are given, in this case the 2 core plus the 3 valence equal 5 total electrons
Neutral elements have the same number of protons and electrons, so your answer would be the element with 5 electrons, Boron.
You can also know this by using electron configuration. Since you kow there are 5 electrons then you can use EC to find out where your element is. In this case it is: 1s2 2s2 2p1
