Answer: 27 neutrons
Explanation:
Recall that the number of protons in the nucleus of an atom = Atomic number.
Hence, Calcium with mass number 47 and atomic number 20 will have 20 protons
Therefore, since Mass number = number of protons + neutrons
47 = 20 + neutrons
Neutrons = 47 - 20 = 27
Thus, there are 27 neutrons in radioactive calcium nucleus.
Answer:
Hydrogen Chloride Gas is heavier than air and sinks to the ground after being released. Firefighters closer to the ground will be subjected to significantly greater concentrations of hydrogen chloride gas than the firefighters walking on top of railcars.
Explanation:
The molar mass of air is 28.97 g/mol. Air is approximately 78% N2, which has a molar mass of 28.014 g/mol and 21% oxygen, which has a molar mass of 32 g/mol; the remaining constituents of air include CO2 and other trace amounts of gases.
The molar mass of HCl is 36.458 g/mol.
Because HCl is heavier than air, it sinks toward the ground, displacing the lighter air.
The height of railway cars is reported to vary between 13.5 ft to 15.5 ft. So firefighters on tank cars are generally above the HCl gas (although localized atmospheric conditions could cause the HCl to move higher up in the air column).
mass defect = mass of constituents - mass of atom
N has 7p and 9n
proton mass ~ 1.00728 amu
neutron mass ~ 1.00866 amu
electron mass ~ 0.000549 amu
Nitrogen mass ~ 14.003074 amu
mass defect = (7*1.00728)-(7*1.00866)-(7*0.000549)
- 14.003074
= 0.11235amu
convert to energy, the binding energy = 1.68x10^-11 J
This is false because catalytic converters in an automobile don't act upon carbon dioxide. They burn carbon monoxide and other carbon gasses to create carbon monoxide and water.
