There should be a sufficient amount of the selected isotope in the rock.
The half-life of the isotope must be long enough to capture the age of the rock.
Explanation:
Sully must consider two main aspect before selecting her choice isotope for dating.
There must be sufficient amount of the selected isotope in the rock.
The half - life of the isotope must be long enough to capture the age of the rock.
- Radiometric dating gives a rock an absolute numerical age.
- The half-life of an isotope is time take for half of a radioactive element to decay.
- If the half-life of an isotope is very short, all the parent nuclide would have turned to daughter nuclides.
- Also, we must have sufficient amount of both the daughter and parent isotope in the selected rock.
learn more:
Radiometric dating brainly.com/question/7022607
#learnwithBrainly
Freezing point depression depends of the number of particles of the solute in the solution.
1)Pure water have highest freezing point. All other solutions with given solutes will have lower temperatures.
2) The more particles of the solute in the solution the lower freezing point is going to be.
<span>b. 1.0 m NaCl ( dissociates and give 2 mol ions (1 mol Na⁺ and 1 mol Cl⁻))
c. 1.0 m K3PO4 (</span>dissociates and give 4 mol ions (3 mol K⁺ and 1 mol PO4³⁻)<span>
d. 1.0 m CaCl2 (</span>dissociates and give 3 mol ions (1 mol Ca²⁺ and 2 mol Cl⁻))<span>
e. 1.0 m glucose (c6h12o6) (glucose does not dissociate, and solution have
1 mole of particles of the solute(glucose))
The largest number of particles has </span>1.0 m K3PO4 solution, and it is has lowest freezing point . Answer is C.
i think it is 8. I might be wrong.
Endothermic reaction is the answer.