Uranium-232 has a half-life of 68.8 years. After 344.0 years, how much uranium-232 will remain from a 375.0-g sample?

Uranium-232 will remain 11.72 g

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.  

Usually radioactive elements have an unstable atomic nucleus.  

The main particles are emitted by radioactive elements so that they generally decay are alpha (α), beta (β) and gamma (γ) particles  

General formulas used in decay:  

T = duration of decay  

t 1/2 = half-life  

N₀ = the number of initial radioactive atoms  

Nt = the number of radioactive atoms left after decaying during T time

t 1/2 = half-life  = 68.8 years

T = duration of decay  = 344 years

No= initial sample = 375 g

Uranium-232 remain :

the answer is definitely c.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8