Answer:
U= 238g/mol
U2O5= 556g/mol
Explanation:
Since U= 238
O=16
U3O5= 2(238)+3(16)=556g/mol
Organisms are living things. Us humans are also living things, so we are helpful and harmful to other organisms. For example: we can help another human being with something, or we can help a plant/tree grow if we water it. In return, they also help us by providing us with oxygen. however, we can also be harmful to each other and the environment, for example: we can't hurt each other, or plant or animals by killing them or we can hurt insects by stepping on them. Therefore, organisms are helpful and harmful to each other.
The element which has the electronic configuration is CHLORINE.
The atomic number of chlorine is 17 and it has 7 valence electrons in its outermost shell. Because it needs only one more electrons to have a stable octet, it usually react with metals from group one of the periodic table who are normally willing to donate the single electrons in their outermost shells. The ground state electronic configuration of chlorine atom is 1S^2 2S^2 2P^6 3S^2 3P^5.
Answer:
See Explanation
Explanation:
Given that;
N/No = (1/2)^t/t1/2
Where;
No = amount of radioactive isotope originally present
N = A mount of radioactive isotope present at time t
t = time taken
t1/2 = half life
N/1000=(1/2)^3/6
N/1000=(1/2)^0.5
N = (1/2)^0.5 * 1000
N= 707 unstable nuclei
Since the value of the initial activity of the radioactive material was not given, the activity of the radioactive material after three months is given by;
Decay constant = 0.693/t1/2 = 0.693/6 months = 0.1155 month^-1
Hence;
A=Aoe^-kt
Where;
A = Activity after a time t
Ao = initial activity
k = decay constant
t = time taken
A = Aoe^-3 *0.1155
A=Aoe^-0.3465
