Biuret reagent will indicate the presence of protein in a given sample. It is also known as the Piotrowski's test. This reagent consists of copper (II) sulfate and sodium hydroxide. It detects peptide bonds by the reaction of the copper ions in an alkaline solution. The copper ions would form violet colored complexes when peptide is present in the solution. From this test, concentration can be calculated since the intensity of the color depends on the amount of peptide bonds and according to the Beer-Lambert law concentration and the absorption of light is proportional. The concentration is calculated by a spectrophotometric technique at a wavelength of 540 nm.
Heat transfer is the phenomenon that occurs when the two objects are in the vicinity of each other and by increasing the area of their contact. Thus, option B is correct.
<h3>What is heat transfer?</h3>
Heat transfer is a process that flows the heat from one system to another, and is because of the difference in the temperature of the two objects that are part of the system.
The methods like conduction, convection, and radiation transfer the heat from the surface area to the other object. The heat gets transferred from the area of high to the low temperature.
Therefore, option B. by increasing the surface area the heat transfer increases.
Learn more about heat transfer here:
brainly.com/question/17823456
#SPJ1
Answer: Chris Brown has launched a charity organization called the Symphonic Love Foundation.
Explanation:
<u>Answer:</u> The pH of the buffer is 4.61
<u>Explanation:</u>
To calculate the pH of acidic buffer, we use the equation given by Henderson Hasselbalch:
![pH=pK_a+\log(\frac{[\text{conjuagate base}]}{[\text{acid}]})](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%28%5Cfrac%7B%5B%5Ctext%7Bconjuagate%20base%7D%5D%7D%7B%5B%5Ctext%7Bacid%7D%5D%7D%29)
We are given:
= negative logarithm of acid dissociation constant of weak acid = 4.70
= moles of conjugate base = 3.25 moles
= Moles of acid = 4.00 moles
pH = ?
Putting values in above equation, we get:

Hence, the pH of the buffer is 4.61