Answer:
mass number = 18
Explanation:
The mass number is the total amount of protons and neutrons in an atom. Therefore, if there are 8 protons and 10 neutrons, the mass number is 18 (8 + 10 = 18).
57.0 is it rounded to three sig figs. You count three spaces then round from there, which would be the zero and you would round down because the four is there.
Answer:
Ozone is a gas made up of three oxygen atoms (O3). It occurs naturally in small (trace) amounts in the upper atmosphere (the stratosphere). Ozone protects life on Earth from the Sun's ultraviolet (UV) radiation.
Answer:
the smallest mass of material that can sustain a chain reaction
Explanation:
Critical mass refers to the smallest possible mass of a fissionable material that can sustain a chain reaction
