Answer:
8 neutrons
A is the number of neutrons plus protons in the nucleus. However, we already know that there are 7 protons. Therefore, there must be 8 neutrons in the nucleus to add up to 15. Table 3.
Element Symbol Number of Neutrons
carbon 146C 8
nitrogen 147N 7
157N 8
oxygen 168O 8
Explanation:
1) the element symbol, and thus name. For example, H is hydrogen, C is carbon and Fe is iron.
2) The atomic number, which is equal to the number of protons in the nucleus.
3) Since each proton has a +1 charge, you can also figure out the number of -1 electrons in the neutral atom.
4) The atomic mass, in atomic mass units, which is an average of 1 or more isotopes of the element.
The last equation you have written out would be the correct single replacement reaction.
The first step is to use the formula from Boyle's Law.
[(351 L)(1.0 atm)]/(181L) = 1.94 atm.
To determine the depth of the location where the diver was working, 1.94 is multiplied by 10. Therefore, the location of the underwater archaeological site is 19.4 meters below the surface.