At STP, one mole of gas occupies 22.4 L of space. Assuming the conditions conform to STP
volume CO2 = 0.5 mol * 22.4 L/1 mol
= 11.2 L
= 10 L
The answer with 1 significant figure is 10 L of CO2
a) Volume percent
Formula: % v/v = [volume solute / volume solution] * 100
Just to make it easy take a base of 50 volume parts of ethylen glycol and 50 volume parts of water to make 100 volumes of mixture (this assumpion will be valid for all the questions):
% v/v =[ 50 ml ethyleneglycol] / [100 ml mixture] * 100 = 50%
Answer: 50% v/v
b) Mass percent
% m/m = [mass ethylene glycol / mass solution] * 100
mass ethylene glycol = 50 ml * 1.114 g/ ml = 55.7 g
mass of mixture = 100 ml * 1.07 g/ml = 107 g
% m/m = [55.7 / 107 g] * 100 = 52.06 %
Answer: 52.06%
c) Molarity
M = number of moles of solute / liters of solution
number of moles of solute = mass in grams / molar mass
number of moles of ehtylene glycol = 55.7 g / 62.07 g/mol = 0.8974 mol
liters of solution = 0.1 liter
M = 0.8974 mol / 0.1 liter = 8.974 M
Answer: 8.974 M
d) Molality
m = number of moles of solute / kg of solvent
number of moles of ethylen glycol = 0.8974 mol
mass of water = 50 ml * 1 g/ml = 50 g = 0.05 kg
m = 0.8974 mol / 0.05 kg = 17.95 m
Answer: 17.95 m
e) mole fraction
mole fraction = [number of moles of solute] / [number of moles of mixture] * 100
number of moles of ethylen glycol = 0.8974 mol
number of moles of water = 50 g / 18.01 g /mol = 2.776 mol
mole fraction = 0.8974 mol / [0.8974 mol + 2.776 mol] = 0.244
Answer: 0.244
The Km is the MIchealis-Menten constant and this represents the affinity of the enzyme to its substrate. The higher the value for Km, the higher is the affinity of the enzyme to a substrate and the greater is the rate of reaction. Hexokinase IV has a higher Km than other hexokinases because it has a higher affinity to hexose substrates.
Answer:
U-238
Explanation:
For a given radioisotope, half life can be defined as the time taken for the isotope to decay into one-half of its original amount. Mathematically, this is expressed as:
where k = rate constant for the radioactive decay process
Greater the t1/2 longer will be its stability.
Based on the given data, U-238 has the largest half life and therefore will be best suited for applications mentioned.
