Answer:
c) There are sharp emission lines demonstrating discrete energy levels.
Explanation:
When an element emits energy in the form of radiation, it produces a spectrum of colors on a photographic plate. This spectrum can either be continuous or discrete. In continuous spectrum the spectrum continues without any discrimination between two regions. This represents the continuous emission of radiation, and thus the continuous emission of energy without any break.
On the other hand, the line spectrum consists of discrete and sharp lines, which shows the emission of radiation in a certain amount in a certain time, with a break between emission. Hence, the line spectra supports the quantization of energy.
The correct option is:
<u>c) There are sharp emission lines demonstrating discrete energy levels.</u>
Answer:
The mass is 0.855 grams (option A)
Explanation:
Step 1: Data given
aluminium sulfate = Al2(SO4)3
Numer of moles Al2(SO4)3 = 2.50 * 10^-3 moles
atomic mass Al = 26.99 g/mol
atomic mass S = 32.065 g/mol
Atomic mass O = 16 g/mol
Step 2: Calculate molar mass Al2(SO4)3
Molar mass = 2* 26.99 + 3*32.065 + 12*16
Molar mas = 342.175 g/mol
Step 3: Calculate mass Al2(SO4)3
Mass Al2(SO4)3 = moles Al2(SO4)3 * molar mass Al2(SO4)3
Mass Al2(SO4)3 = 2.5 *10^-3 moles * 342.175 g/mol
Mass Al2(SO4)3 = 0.855 grams
The mass is 0.855 grams (option A)
B. 6 atoms of carbon C
I would think this is the answer, because one can't just delete or add atoms; otherwise, the equation would be unbalanced. This also abides with the Law of Conservation of Mass.
Plus, I also came to that conclusion because if we look at the net equation of photosynthesis:

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The number of Carbon atoms is 6 on both the reagent's side and the product's side.
The last one should be right