Answer:
U-238
Explanation:
For a given radioisotope, half life can be defined as the time taken for the isotope to decay into one-half of its original amount. Mathematically, this is expressed as:

where k = rate constant for the radioactive decay process
Greater the t1/2 longer will be its stability.
Based on the given data, U-238 has the largest half life and therefore will be best suited for applications mentioned.
Answer:
the % yield is 82%
Explanation:
Given the data in the question,
we know that;
Molar mass of benzil is 210.23 g·mol−1
Molar mass of dibenzyl ketone is 210.27 g·mol−1
Molar mass of tetraphenylcyclopentadienone is 384.5 g·mol−1
Now,
2.0 g benzil = 2 g / 210.23 g·mol−1 = 0.0095 mole
2.2 g dibenzyl ketone = 2.2 / 210.27 = 0.0105 mole
3.0 g of tetraphenylcyclopentadienone = 3 / 384.5 = 0.0078 mole
Now, the limiting reagent is benzil. 0.0095 mole can reacts wiyh 0.0095 mole of dibenzyl ketone
percentage yield = ( 0.0078 mole / 0.0095 mole ) × 100%
= 0.82 × 100%
= 82%
Therefore, the % yield is 82%
Answer;
12 carbon atoms, 22 hydrogen atoms and 11 oxygen atoms.
Explanation:
Using a balanced chemical equation we can identify the number of carbon, hydrogen, and oxygen atoms in sugar.
CxHyOn + 12O₂ → 11 H₂O + 12CO₂
When an equation is completely balanced, then the number of each atom of an element is equal on the reactant side and the product side.
Therefore;
For carbon; x = 12
For Hydrogen; y = (11×2) = 22
For Oxygen; n + (12×2) = 11 + (12×2)
= n + 24 = 11 + 24
n = 11
Therefore the sugar has, 12 carbon atoms, 22 hydrogen atoms and 11 oxygen atoms.
Thus the balanced equation would be;
C₁₂H₂₂O₁₁ + 12O₂ → 11 H₂O + 12CO₂
Geology is the science of Earth.
Ecology is the science of relationship between an organism and its environment.
Astronomy is the science of studying astronomical objects.
Whereas, Phrenology is the study of relating the size of human skull like its size, shapes e.t.c to his/her personality. So, its not a science as there is no scientific relationship between it.