Answer:
All of these are true
Explanation:
A buffer solution in chemistry is a solution that resists changes in pH when an acid or base is added to it. It is a solution that contains a weak acid and its conjugate base (anion) or a weak base and its conjugate acid.
A buffer is able to resist a change in pH due to the conjugate base and conjugate acid of the weak acids and bases contained in them respectively. The conjugate base/acid are present in an equilibrium quantity with their acid/base counterparts and help to neutralize or react with any additional H+ or OH- from an acid or base added to their solution.
However, when a strong acid or base is added to the buffer solution, there is only a slight change which practically does not change the pH of the solution.
Hence, all of the above options about a buffered solution is true.
Answer:
Polar covalent bond
Explanation:
On the basis of electronegativity bond could be ionic bond, polar and non pole covalent bond.
Ionic bond:
It is the bond which is formed by the transfer of electron from one atom to the atom of another element.
Both bonded atoms have very large electronegativity difference. The atom with large electronegativity value accept the electron from other with smaller value of electronegativity. The electronegativity difference between bonded atoms is greater than 1.7.
For example:
Sodium chloride is ionic compound. The electronegativity of chlorine is 3.16 and for sodium is 0.93. There is large difference is present. That's why electron from sodium is transfer to the chlorine. Sodium becomes positive and chlorine becomes negative ion. Both atoms are bonded together electrostatic attraction occur between anion and cations.
Covalent bond:
It is formed by the sharing of electron pair between bonded atoms.
The atom with larger electronegativity attract the electron pair more towards it self and becomes partial negative while the other atom becomes partial positive. There are two type of covalent bond. Polar and non polar covalent bond. When electronegativity difference is 0.4 - 1.7 bond is polar covalent bond when it is less than 0.4 the bond is non polar covalent.
For example:
In CO the electronegativity of oxygen is 3.5 and carbon is 2.5. That's why electron pair attracted more towards oxygen, thus oxygen becomes partial negative and carbon becomes partial positive. and bond is polar covalent.
Answer:
The percent yield of this reaction is 42.1 % (option B)
Explanation:
Step 1: Data given
Theoretical yield of beryllium chloride = 10.7 grams
actual yield of beryllium chloride = 4.5 grams
Step 2: Calculate the percent yield for this reaction
Percent yield = (actual yield / theoretical yield) * 100%
Percent yield = (4.5 grams / 10.7 grams ) * 100 %
Percent yield = 42.1 %
The percent yield of this reaction is 42.1 % (option B)
Answer:
pH = 1.3
Explanation:
pH is used to measure the concentration of hydrogen ions in a solution. It can be calculated as follows:
pH = -log [H+]
Since the given solution is an acid, therefore, the concentration of H+ ions is the same as the molarity/concentration of the solution.
[H+] = 0.05 m
Substitute in the above equation to get the pH as follows:
pH = -log [H+] = -log [0.05] = 1.3
Hope this helps :)
