Answer:
Can you rank the following chemical substances in order of their absolute entropies (So) from lowest (1) to highest (5) at a temperature of 298 K?
a. Al (s)
b. H2O (l)
c. HCN (g)
d. CH3COOH (l)
e. C2H6 (g)
Explanation:
Entropy quantifies the level of disorder within a system.
In solids, the entropy is significantly lower compared to liquids and gases.
The typical order of entropy is:
solids < liquids < gases
In the substances listed, liquid water notably exhibits strong intermolecular hydrogen bonding.
This results in water having comparatively lower entropy.
Next in line is acetic acid.
Among the gaseous components, ethane has higher entropy than HCN due to its weaker intermolecular interactions.
HCN involves some hydrogen bonding.
Thus, the order of entropy is:
Al(s) < CH3COOH (l) < H2O(l) < HCN(g) < C2H6(g)
684 kcal. One mole of glucose weighs roughly 180g. Given that 1g of glucose releases 3.8 kcal, we calculate for 1 mole of glucose: 180g -> 180g * 3.8 kcal/g = 684 kcal.
1 pm equals 10^{-10} cm. Therefore, 230 pm can be converted to 2.3 × 10^{-8} cm. Atoms are spherical in shape, and the volume of a sphere can be calculated using the formula 4/3πr³. Consequently, the atom's volume is calculated as 4/3π(2.3 × 10^{-8})³. Evaluating this gives 4/3 × (3.142 × 12.167 × 10^{-24}), which simplifies to approximately 5.096 × 10^{-23} cm³. Since 1 m³ is equal to 1,000,000 cm³, we find that the volume of the atom is 5.096 × 10^{-29} m³.
The element represented by the nlx notation of 5d2 is hafnium, designated by the symbol hf. It is categorized as a chemical element with the atomic number 72. Hafnium has a chemical resemblance to zirconium and occurs in various zirconium minerals, whereas it is distinct from zirconium which shares some chemical similarities.
