Answer: Option (c) is the correct answer.
Explanation:
Entropy is defined as the degree of randomness. This means that more is the number of collisions taking place between atoms of a substance more will be the randomness.
Therefore, more will be the entropy of substance. We cannot measure the entropy but we can measure the change in entropy of a substance.
A thermometer is a glass tube that contains a liquid column generally mercury, and it is usually used to measure the temperature of human body.
A calorimeter is a device or apparatus that is used in a chemical reaction to measure the amount of heat involved.
Therefore, we can conclude that the student can't measure entropy directly, only an entropy change.
A closed economy<span> is self-sufficient, meaning no imports are brought in and no exports are sent out, the goal being to provide consumers with everything they need from within the </span>economy's borders. An example would be how <span>Brazil's is an unusually </span>closed economy<span> as measured by trade penetration, with exports plus imports equal to just 27.6 per cent of GDP in 2013.</span>
2 mole Na needs 1 mole Cl2
4 mole Na = 2 mole Cl2
The balanced equation
for the reaction is:
6 HNCO(l) →
C3N3(NH2)3(l) + 3 CO2(g)
Convert amount of urea
from kg to moles
Molar Mass of urea = 60.06
g/mol so, 113 kg urea contains
113 kg / 60.06 = 1.88
mol urea
From balanced equation 6
moles of urea yields only 1 melamine, so divide the moles of urea by 6.
1.88 / 6 = 0.313 kmol
melamine
Now multiply 0.313 with
molar mass of melamine that is 126 g/mol
126 x 0.313 = 39.438 kg
Yield of overall
reaction is 73% so multiply 39.438 with 0.73
<span>39.438 x 0.73 = 28.799
kg is the answer</span>
