Answer:
a)Atomic number
Explanation:
Element symbol signifies the element. For eg, Na is sodium. Mass number is the sum of protons and neutrons of an atom of an element. Atomic mass is the molar mass of the given element. Finally, atomic number is unique to each element because it signifies the number of protons of that element. EACH ELEMENT has their UNIQUE number of protons. For eg, atomic number of hydrogen is 1 because it has 1 proton, NO OTHER ELEMENT HAS ATOMIC NUMBER 1 because NO OTHER ELEMENT HAS 1 proton.
Answer: 16.7 gallon
Explanation:
Given: The car can drive 30.3 miles when 1 gallon of gasoline is used.
Distance covered = 506.3 miles
Thus for 30.3 miles, the amount of gasoline used= 1 gallon
For 506.3 miles, the amount of gasoline used=
Thus the amount of gasoline used is 16.7 gallons.
Though the ratio of any two atom's masses was the same on either scale, it was horribly confusing, so in 1961, a compromise was reached. Instead of using either Hydrogen, or Oxygen as the standard, the isotope of Carbon<span> with 6 </span>protons<span> and 6 neutrons in its nucleus (</span>Carbon-12<span>) was given a mass of exactly 12.</span>