Answer:
pH of the final solution = 9.15
Explanation:
Equation of the reaction: HCl + NH₃ ----> NH₄Cl
Number of moles of NH₃ = molarity * volume (L)
= 0.4 M * (300/1000) * 1 L = 0.12 moles
Number of moles of HCl = molarity * volume (L)
= 0.3 M * (175/1000) * 1 L = 0.0525 moles
Since all he acid is used up in the reaction, number of moles of acid used up equals number of moles of NH₄Cl produced
Number moles of NH₄Cl produced = 0.0525 moles
Number of moles of base left unreacted = 0.12 - 0.0525 = 0.0675
pOH = pKb + log([salt]/[base])
pKb = -logKb
pOH = -log (1.8 * 10⁻⁵) + log (0.0525/0.06755)
pOh = 4.744 + 0.109
pOH = 4.853
pH = 14 - pOH
pH = 14 - 4.853
pH = 9.15
Therefore, pH of the final solution = 9.15
Answer:
A. True
B. False
C. False
D. True
E. False
Explanation:
A. The proximal histidine covalently binds iron.
This statement is true because the proximal histidine is covalently bonded to the fifth coordination position of iron in myoglobin
B. The distal histidine covalently binds oxygen.
This statement is false because the distal histidine interacts with the oxygen covalently bonded to the sixty coordination position of iron by means of a hydrogen bond not a covalent bond.
C. The distal histidine binds iron
This statement is false because the distal histidine is not bonded to iron but to oxygen but stabilizes the oxygen bonded to iron
D. Free heme binds CO with the Fe, C and O atoms in a linear array.
This statement is true because free heme has more affinity for CO than O2 as it has the least steric hindrance when the Fe, C, and O atoms lie in a straight line. On the other hand, when O2 binds to free heme, the axis of the oxygen molecule is positioned at an angle to the Fe-O bond thereby producing significant steric hindrance.
E. The iron in heme binds the oxygen atom of CO.
This statement is false because the iron in heme binds to the carbon atom, C, of CO rather than to oxygen atom.
C. Because both reactants and products continue to form.
Answer: electron donor.
Explanation:
According to Arrhenius concept, a base is defined as a substance which donates hydroxide ions 
when dissolved in water and an acid is defined as a substance which donates hydronium ions 
in water.
According to the Bronsted Lowry conjugate acid-base theory, an acid is defined as a substance which donates protons and a base is defined as a substance which accepts protons.
According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.
Here 
acts as lewis base and 
act as lewis acid.
Thus lewis base is defined as an electron pair donor.
