Answer:
i) 16 mL of ethanol
ii) maximum amount recoverable = 15.52 g; percentage recovery = 97%
iii) maximum amount recoverable = 15.1 g
percentage recovery = 94.4%
Explanation:
Solubility = mass/volume
i) mass of ethanol recovered per mL of ethanol when cooled from 78 °C to 0 °C = 0.13 - 0.03 = 0.10 g
Therefore 1.60 g of Y will require a minimum of 1.60 x 1 mL/0.10 g = 16 mL of ethanol
ii) maximum amount of Y that can be recovered is given as :
mass of Y left in solution after recrystallization, x is obtained
0.03 g/mL = x g/16 mL
x = 0.48 g
maximum amount recoverable = 16 - 0.48 = 15.52 g
percentage recovery = (15.52/16) x 100 % = 97%
iii) if 30 mL of ethanol were used:
mass of Y left in solution after recrystallization, x is obtained;
0.03 g/mL = x g/30 mL
x = 0.03 x 30 = 0.9 g
maximum amount recoverable = 16 - 0.9 = 15.1 g
percentage recovery = (15.1/16) x 100% = 94.4%
Answer:
Option (C).
Explanation:
ATP is the energy currency of the cell that are directly used by the cell. ATP helps in the contraction of muscles, propagation of the nerve impulse and in the chemical synthesis of the molecules.
The ATPase enzyme is required for the hydrolysis of the ATP molecule. The ATPase hydrolyzes the third phosphate group and not the first phosphate group when the energy is needed. The gamma or third phosphate first removed during ATP hydrolysis.
Thus, the correct answer is option (C).
Answer:
opposite of a proton is an electron
<span>60. 4Li(s) + O2(g) >>>>>>>>>>> 2Li2O(s)
moles O2 required = (84 grams Li) * (1 mol Li / 6.941 grams Li) * (1 mol O2 / 4 mol Li) = 3.026 moles O2 required.
PV = nRT, P = 1 atm, V = ?, n = 3.026 moles, R = 0.0821 L*atm/mol*K, T = 273 K
(1 atm)*(V) = (3.026 moles O2) * (0.0821 L*atm/mol*K) * (273 K)
V = 67.82 Liters is the answer.
hope this helps</span>