There are two ways to solve this problem. We can use the ICE method which is tedious and lengthy or use the Henderson–Hasselbalch equation. This equation relates pH and the concentration of the ions in the solution. It is expressed as
pH = pKa + log [A]/[HA]
where pKa = - log [Ka]
[A] is the concentration of the conjugate base
[HA] is the concentration of the acid
Given:
Ka = 1.8x10^-5
NaOH added = 0.015 mol
HC2H3O2 = 0.1 mol
NaC2H3O2 = 0.1 mol
Solution:
pKa = - log ( 1.8x10^-5) = 4.74
[A] = 0.015 mol + 0.100 mol = .115 moles
[HA] = .1 - 0.015 = 0.085 moles
pH = 4.74 + log (.115/0.085)
pH = 4.87
Answer:
The α‑helix is held together by hydrogen bonds between the amide N−H and C=O groups.
Disulfide bonds stabilize secondary structure.
Explanation:
Proteins have primary, secondary, tertiary and quartinary structures.
The secondary structure of a protein is the regular, recurring sequence of amino acid in a polypeptide chain. Secondary structure of proteins give rise to the folding observed in the structure of a protein.
The major secondary structures of a protein are α-helices and β-structures.
Answer:
64799.4 J
Explanation:
The following data were obtained from the question:
Mass (M) = 1.05 kg = 1.05 x 1000 = 1050g
Specific heat capacity (C) = 0.9211 J/g°C
Initial temperature (T1) = 23°C
Final temperature (T2) = 90°C
Change in temperature (ΔT) = T2 – T1 =
90°C – 23°C = 67°C
Heat required (Q) =....?
The heat required to increase the temperature of the kettle can b obtain as follow:
Q = MCΔT
Q = 1050 x 0.9211 x 67
Q = 64799.4 J
Therefore, 64799.4 J of heat is required to increase th temperature of the kettle from 23°C to 90°C.
Answer:
Na+
Explanation:
The equation would be:
HCl (aq) + NaOH (aq) --> HOH (l) + NaCl (aq)
The equation is already balanced and the NaCl will disassociate in Na+ and Cl- and HCl will disassociate into H+ and Cl- and NaOH will disassociate into Na+ and OH-. Na+ is on both sides of the equation and stays the same, so Na+ will be the spectator ion.
Answer: The percent yield for the 
is, 86.7 %
Explanation : Given,
Moles of 
= 2.36 mol
Moles of = 6.14 mol
First we have to calculate the moles of
The balanced chemical equation is:
From the reaction, we conclude that
As, 2 moles of react to give 6 moles of
So, 2.36 moles of react to give 
mole of
Now we have to calculate the percent yield for the .
Experimental yield = 6.14 moles
Theoretical yield = 7.08 moles
Now put all the given values in this formula, we get:
Therefore, the percent yield for the is, 86.7 %
