Atomic mass silicon = 28.085 u
1 mol Si ---------------- 28.085 g
? ------------------------ 245 g
245 x 1 / 28.085 => 8.72 mol
answer A
Answer:
The group number in the periodic table represents number of valence electrons of the elements in a certain group.
Explanation:
There are s, p, d, and f blocks, which you can see in periodic table
The s-block and p-block together are usually considered main-group elements, the d-block corresponds to the transition metals, and the f-block encompasses nearly all of the lanthanides (like lanthanum) and the actinides (like actinium)
There are three main principles, which may useful for you:
- The Pauli exclusion rule basically says that at most, 2 electrons are allowed to be in the same orbital.
- Hund’s rule explains that each orbital in the subshell must be occupied with one single electron first before two electrons can be in the same orbital.
- The Aufbau process describes the process of adding electron configuration to each individualized element in the periodic table.
Hope this helps!
Answer:
I would say A. I'm no expert, but it can't be C obviously, and I think wind would hit all of it, wearing off the top as well like the great pyramids. B would be my next choice, but A i think would be best.
Soluble means it can be dissolved
Insoluble means it can't be dissolved
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 %.
