Density = mass / volume
Density = 7.5 g / 5.0 cm3
Density = 1.5 g/cm3
Google said
How many electrons fit in each shell around an atom?
The maximum number of electrons that can occupy a specific energy level can be found using the following formula:
Electron Capacity = 2n2
The variable n represents the Principal Quantum Number, the number of the energy level in question.
Energy Level
(Principal Quantum Number) Shell Letter Electron Capacity
1 K 2
2 L 8
3 M 18
4 N 32
5 O 50
6 P 72
Keep in mind that an energy level need not be completely filled before electrons begin to fill the next level. You should always use the Periodic Table of Elements to check an element's electron configuration table if you need to know exactly how many electrons are in each level.
Use formula: Initial Pressure x Initial Volume/Initial temperature = Final pressure x Final Volume/Final Temperature => 17.15L
Cs -137 has a half life of about 30 years. If 60 years pass, there is two half lives passed so 1/2 * 1/2= 1/4. Take 1/4 and multiply it with the mass given:
(1/4)*20mg=5mg left
Answer:
hydrogen and oxygen to form water