Answer:
Number of moles = 2.89 mol
Explanation:
Given data:
Number of moles of sugar = ?
Mass of sugar = 990 g
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of C₁₂H₂₂O₁₁:
12× 12 + 22×1.008 + 16×11 = 342.2 g/mol
Number of moles = 990 g / 342.2 g/mol
Number of moles = 2.89 mol
Answer: option d
Explanation:
Project teams must be proactive. Each member of the team should empowered and each member can share ideas and experience in order to make the WBS more precise.
Answer:

Explanation:
First thing is we have assume all the percents are grams so we have
68.279g C, 6.2760g H, 3.7898g N, and 21.656g O
Now convert each gram to moles by dividing the the molar mass of each element
68.279g/12.01g= 5.685 moles of C
6.2760g/1.01g= 6.214 moles of H
3.7898g N/14.01g= 0.271 moles of N
21.656g O/ 16.00g= 1.354 moles of O
Now to find the lowest ratios divide all the moles by the smallest number of moles you found, in our case, the smallest moles is 0.271 moles of N so divide everything by that....
5.685 moles/0.271 moles ------> ~21 C
6.214 moles/0.271 moles --------> ~23 H
0.271 moles / 0.271 moles ---------> 1 N
1.354 moles/ 0.271 moles ----------> ~5 O
So the empirical formula is C21H23NO5 
Dalton postulated that atoms of the same elements had the same mass while atoms of different elements had different masses.
The discovery of isotopes revealed that atoms of the same element did not necessarily have same masses, they could have different masses.
Therefore, the modern periodic table that we use nowadays contains the average atomic mass of all the isotopes found for a given element.