Equivalence point on titration curves.

Titration is a laboratory procedure where a known base is added to unknown acid (or vise versa) to figure out the molarity of the unknown. When the base completely neutralizes acid, an equivalence point has been reached. Equivalence point pH depends on the strength of the acid and base involved in the titration. For a strong acid/ strong base titration, equivalence point pH will be 7, since all of the acid will be completely neutralized by the base. For a strong acid/ weak base titration, at equivalence point there will be conjugate acid left, and therefore pH will be slightly acidic, below 7. For a strong base/ weak acid titration, at equivalence point there will be conjugate base left, and

How do intermolecular forces affect vapor pressure?

What is vapor pressure? The simple way to understand it, is to realize that pressure is caused by gas (in our case vapor). The more gas there is, the higher the pressure is. Vapor pressure is the pressure of the gas above the liquid. The more vapor there is above, the higher the vapor pressure is. Intermolecular forces are attractive forces between molecules. The stronger the intermolecular forces, the more attracted the molecules in liquid are to each other and the harder it is to separate them to turn into gas (vapor). Therefore, for a liquid with strong intermolecular forces, not a lot of vapor will be formed and the vapor pressure will be low. A liquid with weak intermolecular forces, su

What is the oxidation number of N in KNO3?

In order for us to find oxidation numbers, we need to learn some oxidation rules first. Oxidation rules: 1. Oxygen is -2, unless in peroxides. 2. Group 1 metals = +1 3. Group 2 metals = +2 4. If the molecule is neutral, all of the oxidation numbers have to add up to zero. 5. If the molecule is charged, all of the oxidation numbers have to add up to the charge of the molecule. When it comes to calculation the oxidation number of N in KNO3, we can make a small equation. From our rules we know that O= -2 and we can find K on the periodic table, in the first group, thus giving it a +1 charge. Now let's put it all together. K=+1 N=x O=-2. Let's take into account the number of atoms of each elemen

What is the equilibrium constant?

Many reactions do not go to completion, where all of the reactants turn into products and the reaction is over. Instead, most reactions reach a state called equilibrium. At equilibrium, reactants turns into products at the same rate as products turn into reactants. Therefore, both forward and reverse reactions keep on going. Equilibrium constant, Keq, gives a ratio of the concentration of products to reactants (Keq= [products]/[reactants]). Thus, equilibrium constant tells us at equilibrium whether the formation of products or reactants is favored. A high equilibrium constant tells us that at equilibrium, formation of products (or the forward reaction) is favored because in order for a rati

Which compounds are soluble in water?

Water, H2O is a polar molecule (not symmetric) and has Hydrogen bonding (due to OH). There is a rule that says like dissolves like. Therefore, molecules that are polar will dissolve in water, and those that are not polar, will not. For example, O2 is a non polar molecule and will not dissolve in water. CH3OH is a polar molecule and will therefore dissolve in water. Ionic compounds (metal+nonmetal) will also dissolve in water and dissociate into ions. For example, NaCl is very soluble in water. To learn more chemistry topics with our amazing chemistry tutors in NYC, Brooklyn and online, please call 6464079078. #chemistrytutor