Answer:
A
Explanation:
The mass number (represented by the letter A) is defined as the total number of protons and neutrons in an atom. Consider the table below, which shows data from the first six elements of the periodic table. Consider the element helium. Its atomic number is 2, so it has two protons in its nucleus.
50x75=3750 -- metres per day
3750x15=56250 -- metres in 15 days
Divide by 1000 to convert to km
56.250km
<u>56.25km</u>
Answer:
The atomic radius of atoms generally decreases from left to right across a period. There are some small exceptions, such as the oxygen radius being slightly greater than the nitrogen radius. Within a period, protons are added to the nucleus as electrons are being added to the same principal energy level.
hope this helps!
The name of the compound K3N is potassium nitride (C).
Pressure caused by high temperatures are balanced by gravity
