Complete Question
You determine that it takes 26.0 mL of base to neutralize a sample of your unknown acid solution. The pH of the solution was 7.82 when exactly 13 mL of base had been added, you notice that the concentration of the unknown acid was 0.1 M. What is the pKa of your unknown acid?
Answer:
The pK_a value is
Explanation:
From the question we are told
The volume of base is 
The pH of solution is 
The concentration of the acid is 
From the pH we can see that the titration is between a strong base and a weak acid
Let assume that the the volume of acid is 
Generally the concentration of base

Substituting value


When 13mL of the base is added a buffer is formed
The chemical equation of the reaction is

Now before the reaction the number of mole of base is
![No \ of \ moles[N_B] = C_B * V_B](https://tex.z-dn.net/?f=No%20%5C%20of%20%5C%20moles%5BN_B%5D%20%20%3D%20%20C_B%20%2A%20V_B)
Substituting value

Now before the reaction the number of mole of acid is

Substituting value


Now after the reaction the number of moles of base is zero i.e has been used up
this mathematically represented as

The number of moles of acid is


The pH of this reaction can be mathematically represented as
![pH = pK_a + log \frac{[base]}{[acid]}](https://tex.z-dn.net/?f=pH%20%20%3D%20pK_a%20%2B%20log%20%5Cfrac%7B%5Bbase%5D%7D%7B%5Bacid%5D%7D)
Substituting values

In thermal cracking, high temperatures (typically in the range of 450°C to 750°C) and pressures (up to about 70 atmospheres) are used to break the large hydrocarbons into smaller ones. Thermal cracking gives mixtures of products containing high proportions of hydrocarbons with double bonds - alkenes.
Answer:
The answer is in the photo
Explanation:
I hope that is useful for you :)
Answer:

Explanation:
We are given the mass, specific heat, and temperature, so we must use this formula for heat energy.

The mass is 5 grams, the specific heat capacity is 0.14 Joules per gram degree Celsius. Let's find the change in temperature.
- ΔT= final temperature - initial temperature
- ΔT= 95°C - 15°C = 80°C
We know the variables and can substitute them into the formula.


Multiply the first numbers. The grams will cancel.

Multiply again. This time the degrees Celsius cancel.

56 Joules of heat are needed.
Answer:
The rearrangement of particles in a physical change.
Explanation:
When things are liquid the particles tend to be spread out because they aren't tightly compacted as they would be with a solid. So when liquid gold is changing from a liquid to a solid the properties are changing and the particles in the gold are getting closer together.