(2) U-238 is the radioisotope used in dating geological formations. Uranium-238 has a half-life of 4.46 billion years, which makes it suitable to date such old formations.
The other options do not have such long durabilities and half-lives.
Chemical equation represents a redox reaction :
2Li + MgCl₂ → 2LiCl + Mg
<h3>Further explanation</h3>
The oxidation-reduction reaction or abbreviated as Redox is a chemical reaction in which there is a change in oxidation number
Reaction
2Li + MgCl₂ → 2LiCl + Mg
Oxidation is an increase in oxidation number, while reduction is a decrease in oxidation number.
Oxidation

Reduction

Answer: The answer is True
Explanation: I hope my answer helps :)
Answer:
0.252 milimoles
Explanation:
To convert mass of a substance to moles it is necessary to use the molar mass of the substance.
The formula of morphine is C₁₇H₁₉NO₃, thus, its molar mass is:
C: 17*12.01g/mol = 204.17g/mol
H: 19*1.01g/mol = 19.19g/mol
N: 1*14g/mol = 14g/mol
O: 3*16g/mol = 48g/mol.
204.17 + 19.19 + 14 + 16 = <em>285.36g/mol</em>
Thus, moles of 71.891 mg = 0.071891g:
0.071891g × (1mol / 285.36g) = 2.5193x10⁻⁴ moles
As 1 mole = 1000 milimoles:
2.5193x10⁻⁴ moles = <em>0.252 milimoles</em>