For radioactive decay, we can relate current amount, initial amount, decay constant and time using:
N = No x exp(-λt)
Half-life = ln(2)/λ
λ = ln(2) / 5730
N/No = 80% = 0.8
0.8 = exp( -ln(2)/5730 x t)
t = 1844 years
Answer:
Measuring its density and comparing your result to a list of known densities, or other properties that give you useful info
Explanation:
You can use observations about substances to form a hypothesis about the substance by comparing it to others. Ex: if something is magnetic it must be made of one or more of the elements iron, cobalt, or nickel.
The question is asking us to determine what gives the Amethyst its purplish color. Amethyst colors range from light to dark purple. The most highly regarded are the transparent deep purple colors. Amethyst ( chemical formula: Si O2 ) is the purple variety of the mineral Quartz.The pure Quartz is often colorless. Amethyst gets its purplish color because of the presence of Iron ( Fe ) and other impurities in the gem. Answer: C. Iron.<span /><span />
It is too early for students to have career preferences while still in school
(i believe) <span />
