The question is incomplete, here is the complete question:
Calculate the pH of a solution prepared by dissolving 0.370 mol of formic acid (HCO₂H) and 0.230 mol of sodium formate (NaCO₂H) in water sufficient to yield 1.00 L of solution. The Ka of formic acid is 1.77 × 10⁻⁴
a) 2.099
b) 10.463
c) 3.546
d) 2.307
e) 3.952
<u>Answer:</u> The pH of the solution is 3.546
<u>Explanation:</u>
We are given:
Moles of formic acid = 0.370 moles
Moles of sodium formate = 0.230 moles
Volume of solution = 1 L
To calculate the molarity of solution, we use the equation:
To calculate the pH of acidic buffer, we use the equation given by Henderson Hasselbalch:
![pH=pK_a+\log(\frac{[salt]}{[acid]})](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%28%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7D%29)
![pH=pK_a+\log(\frac{[HCOONa]}{[HCOOH]})](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%28%5Cfrac%7B%5BHCOONa%5D%7D%7B%5BHCOOH%5D%7D%29)
= negative logarithm of acid dissociation constant of formic acid = 3.75
![[HCOONa]=\frac{0.230}{1}](https://tex.z-dn.net/?f=%5BHCOONa%5D%3D%5Cfrac%7B0.230%7D%7B1%7D)
![[HCOOH]=\frac{0.370}{1}](https://tex.z-dn.net/?f=%5BHCOOH%5D%3D%5Cfrac%7B0.370%7D%7B1%7D)
pH = ?
Putting values in above equation, we get:
Hence, the pH of the solution is 3.546
<span>A physical change basically involves a change in physical properties. Some examples of physical properties include: texture, shape, size, color, volume, mass, weight, etc.
The water melting has changed the shape and therefore it's physical properties, but the chemical nature of the water has not been altered.
So that's why it's a physical change, and not a chemical change.</span>
Answer:
Yes
Explanation:
A gene pool is the sum total of all the genes(sum of alleles)of a species and population at any given time is known as gene pool.
The new species are created in nature by four mechanisms such as geographic isolation (allopatric speciation), reproductive isolation (sympatric speciation), mating behaviour (parapatric speciation).
Due to any of these factors when population acquire unique changes in their genes and enough changes have been introduced in the gene pool of the population with time, two population become distinct from each other and not able to interbreed leads to the formation of new species.
Answer:
Tetrahedral
Explanation:
For the repulsion of the free electron pair theory, the shape of a molecule will be to repel the bonds and the free electrons on the central atom. In a molecule of carbon tetrachloride, the central atom (C) has no free electrons, so, the shape that repels better the charge is tetrahedral, as shown below.
