Answer:
40.68 % C
23.73 % N
8.47% H
27.12% O
Explanation:
The mass percent of an element X in a compound is calculated as the molar mass (MM) of X multiplied by the number of atoms of X in the compound, divided into the molecular weight (MW) of the compound, as follows:
mass percent of X = (MM(X) x number of atoms of X)/MW compound x 100
Thus, we first calculate the MW of acetamide (C₂H₅NO) by using the molar mass of the chemical elements C, H, N and O:
MW(C₂H₅NO) = (12 g/mol C x 2) + (1 g/mol H x 5) + 14 g/mol N + 16 g/mol O = 59 g/mol
Now, we can calculate the mass percent of each element (C, H, N, O) in C₂H₅NO:
- Mass percent of C (2 atoms of C in 1 molecule of C₂H₅NO):
% mass C = (12 g/mol x 2)/(59 g/mol) x 100 = 40.68 %
- Mass percent of N (1 atom of N in 1 molecule of C₂H₅NO):
% mass N = (14 g/mol x 1)/(59 g/mol) x 100 = 23.73 %
- Mass percent of H (5 atoms of H in 1 molecule of C₂H₅NO):
% mass H = (1 g/mol x 5)/(59 g/mol) x 100 = 8.47 %
- Mass percent of O (1 atom of O in 1 molecule of C₂H₅NO):
% mass O = (16 g/mol x 1)/(59 g/mol) x 100 = 27.12 %
The sum of the mass percents has to be equal to 100%:
40.68 % C + 23.73 % N + 8.47% H + 27.12% O = 100%
Number of valence electrons (they all have 7 valence electrons)
Answer:
The chemical reaction by which plants produce complex food molecules (sugars) requires an energy input (i.e., from sunlight) to occur. In this reaction, carbon dioxide and water combine to form carbon-based organic molecules and release oxygen.
Explanation:
so basically plants create oxygen and If there were no plants on the planet we wouldn't be able to breathe.
and yes it could be changing since large quantities of trees are cut down every day in rainforests which produce large amounts of oxygen for us. hope this helps!