Answer: 0.25 mol
Explanation:
Use the formula n=N/NA
n= number of mols
N = number of particles
Nᵃ = Avogadros constant = 6.02 x
So, n=
The 10 to the power of 23 cancels out and you are left with 1.505/6.02, which is approximately 1/4. This is the same as 0.25 mol.
Hope this helped :)
"The other halogens are not as electronegative and so other hydrogen halides cannot form hydrogen bonds between molecules. Only London Forces are formed. - Therefore more energy is required to break the intermolecular forces in HF than the other hydrogen halides and so it has a higher boiling point."
not a hack link, just stating where i got your answer from! -
https://www.mytutor.co.uk/answers/17558/A-Level/Chemistry/Explain-the-unusually-high-boiling-point-of-HF/
Explanation:
Given that,
Mass number, A = 302
Atomic number, Z = 119
We know that, atomic number = no of protons
Protons = 119
Mass no. = No. of neutrons + No. of protons
302 = No. of neutrons + 119
No. of neutrons = 302 - 119
= 183
No. of electrons = No. of protons
= 119
Answer: The mass percent of hydrogen in ascorbic acid is 4.5 %
Explanation:
In
, there are 6 carbon atoms, 8 hydrogen atoms and 6 oxygen atoms.
To calculate the mass percent of element in a given compound, we use the formula:

Mass of hydrogen = 
Molar Mass of ascorbic acid =
Putting values in above equation, we get:

Hence, the mass percent of of hydrogen in ascorbic acid is 4.5 %.
Answer:
ΔS> 0 means Letter A
Explanation:
Processes that involve an increase in entropy of the system (ΔS > 0) are very often spontaneous; however, examples to the contrary are plentiful. By expanding consideration of entropy changes to include the surroundings, we may reach a significant conclusion regarding the relation between this property and spontaneity. In thermodynamic models, the system and surroundings comprise everything, that is, the universe, and so the following is true:
\displaystyle \Delta {S}_{\text{univ}}=\Delta {S}_{\text{sys}}+\Delta {S}_{\text{surr}}