Answer:
450. g of 0.173 % KCN solution contains 779 mg of KCN.
Explanation:
Mass of the solution = m
Mass of the KCN in solution = 779 mg
Mass by mass percentage of KCN solution = 0.173%



1 mg = 0.001 g
m = 450,289 mg × 0.001 g = 450.289 mg ≈ 450. g
450. g of 0.173 % KCN solution contains 779 mg of KCN.
Answer: The answer is Fossil A is younger than the index fossil.
Explanation: Because it’s the newest layer
In a beta emission, the mass number of the daughter nucleus remains unchanged while the atomic number of the daughter nucleus increases by one unit. The following are isotopes produced when the following undergo beta emission;
1) potassium-42 ------> Ca - 42
2) iodine-131 ------------> Xe - 131
3) iron-52 ---------------> Co - 52
4) sodium-24 -----------> Mg -24
The daughter nucleus formed after beta emission is found one place after its parent in the periodic table.
Regarding the stability of the daughter nuclei, a nucleus is unstable if the neutron-proton ratio is less than 1 or greater than 1.5.
Hence, the following daughter nuclei are stable; Ca - 42, Xe - 131, Mg -24.
Learn more: brainly.com/question/1371390