The amount of energy is constant, but it is converted from one form to another.
Answer:
12
Explanation:
If you look at the periodic table, you can see that magnesium has an atomic mass of 24.305. Subtract the number of protons from this to get neutrons.
24.305 - 12 = 12.305
12.305 is the average amount of neutrons a magnesium atom can have. A magnesium atom can have 12, 13, or 14 neutrons. The average, based on the natural abundance, is 12.305. To find which isotope is more abundant, you need to pick the number that is closest to the average. This would make the most abundant isotope the one with 12 neutrons.
The mass of the liquid is 4.8 kg.
6.4 L = 6400 mL
Mass = 6400 mL × (0.70 g/1 mL) = 4500 g = 4.8 kg
The notations representing the different isotopes of the element sodium are:
4) 22Na and 23Na
The total number of recognized isotopes of sodium is 20. It starts from 18Na upto 37Na with two isomers (22mNa and 24mNa).
23Na is considered as monoisotopic element meaning it has a single stable isotope making it primordial isotope. 23Na is a single isotope since earth was formed. It has a standard atomic mass of 22.989 769 28(2) u.
22Na, a positron-emitting isotope with a long half life = 2.605 years. It is used to create test objects and point sources for PET or positron emission tomography.