Answer:
1. Ice at 0 degrees C.
2. N₂ at STP.
3. N₂ at STP.
4. Water vapor at 150 degrees C and 1 atm.
Explanation:
First, we need to remember that entropy (S) is a <em>measure of how spread out or dispersed the energy of a system is among the different possible ways that system can contain energy</em>. The greater the dispersal, the greater is the entropy.
When the temperature is increased, the energies associated with all types of molecular motion increase. Consequently, the entropy of a system always increases with increasing temperature.
With this in mind, we consider the pairs:
1. Since the ice at 0ºC has a greater temperature than the ice at -40 ºC, the first has the higher entropy.
2. The N₂ at STP (that is, 1 atm and 25 ºC) has higher entropy than N₂ at 0ºC and 10 atm because it has a higher temperature and less pressure, which allows a greater dispersal of energy by the molecules of the gas.
3. The N₂ at STP has a higher entropy since it has a higher temperature than N₂ at 0ºC, even though it the first has a lower volume (24,4 L vs. 50 L).
4. The water vapor at 150 ºC and 1 atm have a higher temperature and a lower pressure. This means that its molecules will have an increased molecular motion than the molecules of water vapor at a lower temperature and higher pressure. Therefore, the first has the highest entropy.
I think the correct answer from the choices listed above is option A. The additional piece of information needed to determine the molecular formula would be percent composition of carbon. A molecular formula is <span>a formula that gives the number of atoms of each of the elements present in one molecule of a specific compound.</span>
In an aqueous solution, the hydronium ion concentration is equivalent to the hydrogen ion concentration because the hydrogen ion exists as the hydronium ion. The pH of pure water is 7, and:
pH = -log[H+]
7 = -log[H+]
[H+] = 1 x 10⁻⁷
Therefore, the hydronium ion concentration in pure water is also 1 x 10⁻⁷.
The known constant of water is that it freezes at 0 degrees Celsius and boils at 100 degrees Celsius. it can be determined that because of the solute added the water becomes a compound meaning it no longer has the constants of pure water hence the difference in freezing point
