Explanation:
density(d) = mass(m) × volume(v)
given:
mass = 4.3 g = 0.0043 Kg
volume = 2.7 cm³ = 0.027 m³
= 0.0043 Kg / 0.0027 m³
= 0.15 Kg/m³
For a and b, you need to divide it by Avogadro’s number to find the answer.
a. (6.022x10^23)/6.022x10^23 = 1 mole of Ne
b. (3.011x10^23)/6.022x10^23 = 0.5 moles of Mg
For c and d, you’ll use the mass provided divided by the molar mass to find the number of moles.
Pb molar mass = 207.2 g/mol
c. (3.25x10^5)/207.2 = 1.57x10^3 moles of Pb
For d, I can’t tell if is Cu, C or something else but you can follow the steps above to solve the problem.
Explanation:
miscible liquids: water and alcohol
immiscible liquids: water and oil
This question is dealing with the half-life of carbon-14 which can be used to determine the age of a substance according to the following equation:
t = [ln(N/No)/(-ln2)] · t1/2
N = # of carbon-14 atoms presently = 250 atoms
No = # of carbon-14 atoms initially = 1000 atoms
t1/2 = half-life = 5730 years for carbon-14
We can now input all of the information into the formula to find the age of the fossil:
t = [ln (250/1000)/-ln2] x 5730 years
t = 11460 years
The fossil should be found to be roughly 11,460 years old.
