A. 6 NaOH + 2(NH4)3 PO4 -----> 2Na PO4 + 6H2O + 6NH3
b. C2 H6 O + 3O2 ----> 2CO2 + 3H2O
Answer:
A protein has four subunits whose molecular masses are 140, 80, and 60 kDa.
A disulfide bond links the two 80 kDa subunits (possibly identical).
Explanation:
Given that:
A protein has four subunits whose molecular masses are 140, 80, and 60 kDa.
A disulfide bond links the two 80 kDa subunits (possibly identical).
As a result of SDS and dithiothreitol analysis treatment, the molecular masses can not be 360 in total. They are 280, which implies that they are in short of 80 kDa. This means that there are possibilities that two groups with a molecular mass of 80 kDa which are joined by a disulfide bond.
The presence of SDS and dithiothreitol acts as a reducing agent, and they can break disulfide bonds whose pH is greater than 7, i.e. those in basic condition.
P₄O₁₀ + 6H₂O → 4H₃PO₄
The equation shows us that the molar ratio of
P₄O₁₀ : 6H₂O = 1:6
We also know that one mole of a substance contains 6.02 x 10²³ particles. We can use this to calculate the moles of water.
moles(H₂O) = (5.51 x 10²³) / (6.02 x 10²³)
= 0.92 mole
That means moles of P₄O₁₀ = 0.92 / 6
= 0.15
Each mole of P₄O₁₀ contains 4 moles of P.
moles(P) = 4 x 0.15 = 0.6 mol
Mr of P = 207 grams per mol
Mass of P = 207 x 0.6
= 124.2 grams
