Download Calculating Neutrons

Calculating Neutrons
Number of
=
Neutrons
Atomic Mass – Atomic Number
(Atomic Mass minus Atomic Number)
Remember: When rounding numbers to the nearest whole number, you round UP if the
number in the 10ths place is 5-9(like 1.6 would round up to 2) and you round DOWN if the
number in the 10ths place is 0-4 (like 5.4 would round down to 5).
1. Helium (chemical symbol: He)
a. Atomic Mass (rounded) =
b. Atomic Number =
Work:
(Atomic Mass minus Atomic Number = Number of Neutrons)
Number of Neutrons in Helium:
2. Phosphorus (chemical symbol: P)
a. Atomic Mass (rounded) =
b. Atomic Number =
Work:
(Atomic Mass minus Atomic Number = Number of Neutrons)
Number of Neutrons in Phosphorus:
3. Neon (chemical symbol: Ne)
a. Atomic Mass (rounded) =
b. Atomic Number =
Work:
(Atomic Mass minus Atomic Number = Number of Neutrons)
Number of Neutrons in Neon:
4. Carbon (chemical symbol: C)
a. Atomic Mass (rounded) =
b. Atomic Number =
Work:
(Atomic Mass minus Atomic Number = Number of Neutrons)
Number of Neutrons in Carbon:
5. Lithium (chemical symbol: Li)
a. Atomic Mass (rounded) =
b. Atomic Number =
Work:
(Atomic Mass minus Atomic Number = Number of Neutrons)
Number of Neutrons in Lithium: