Answer:
2.3125g
Explanation:
Half-life referred to the time required for a quantity to reduce to half of its initial value, It used to calculate how unstable atoms undergo, or the period of time and atom can survive, radioactive decay.
Given:
t(1/2)= 9.25days
Initial mass of Thulium-167 = 48grams
We need to calculate the remaining amount after 37days.
Since we know that 1 half life = 9.25 days
Then 37 days means ( 37/9.25) half lives
37days means 4 half life
That means the 38grams of Thulium-167 will be halved by 4 times.
Then the ratio between the initial Amount and the amount remaining after 37 days can be calculated as. 0.5^(4)
= 37days × 0.5^(4)
= 2.3125g
the remaining amount of Thallium-167 after 37days is 2.3125g
The Formula of Acetone is

To find the Mass Molar of a compound, you add the Atomic weights of it's atoms.
If you check the Periodic table:
Atomic Weight of Carbone C: 12.0107
Atomic Weight of Hydrogen: 1.00794
Atomic Weight of Oxygen: 15.9994
So, you got:
Total Atomic Weight of Carbone in Acetone: 12.0107 * 3 = 36.0321
Total Atomic Weight of Hydrogen in Acetone: 1.00794 * 6 = 6.04764
Total Atomic Weight of Oxygen in Acetone = 15.9994 * 1 = 15.9994
Now, you add this numbers
36.0321 + 6.04764 + 15.9994 = 58.07914
So, the Molar Mass of Acetone is 58.09714 g/mol
Hope this Helps :D
Lewis structure :
•• •• ••
:Cl• •N • •Cl:
•• • ••
•
:Cl:
••
The dots around the respective atoms represent the number of valence electrons each of the corresponding atoms have. Since nitrogen is more electronegative it is placed within the middle, it can also form the 3 covalent bonds, unlike chlorine which can only form 1 and thus is in the middle of the diagram. This structure has gained stability in that all of the atoms have 8 electrons in its outermost shell, if you were to count the shared electrons for each atom.