Answer: D.atomic mass.
Explanation: The general representation of an element is given by: 
X = chemical symbol of element
Z= atomic number= which represents the number of electrons.
A= mass number or atomic mass =which represents the number of electrons + number of neutrons
Thus mass number is greater than number of electrons and number of neutrons as it is the sum of both.
The correct statement to fill the blank would be the first option. Atomic energy is the energy in the nucleus of an atom of electrons and their shells. From the word atomic itself, we can say that this energy is energy within and carried by the atoms.
51.41%
Percentage Composition from Formulas
A more complex example is sucrose (table sugar), which is 42.11% carbon, 6.48% hydrogen, and 51.41% oxygen by mass.
Or
53.3 %
Thus the % composition of glucose by mass is carbon 40.0 % oxygen 53.3 % hydrogen 6.7 % In this way, the % composition by mass of any compound can be calculated provided that its formula is known.
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What is the percentage composition of sugar?
Element Symbol Mass Percent
Hydrogen H 6.714%
Carbon C 40.001%
Oxygen O 53.285%
Answer:
plz, search it from Google
Explanation:
it is too brief to type
O2 and O3 are allotropes of Oxygen, therefore they have (4) different chemical and physical properties.