Answer:
0.8833 mole of C3H8
Explanation:
Given:
Mass of C₃H₈ (Propane) = 38.95 gram
Computation:
Molar mass of C = 12.01
Molar mass of H = 1.008
Molar mass of C₃H₈ (Propane) = 3(12.01) + 8(1.008)
Molar mass of C₃H₈ (Propane) = 36.03 + 8.064
Molar mass of C₃H₈ (Propane) = 44.094
Number of mol in 38.95 gram Propane = Mass / Molar mass
Number of mol in 38.95 gram Propane = 38.95 / 44.094
Number of mol in 38.95 gram Propane = 0.88334
1. color of the rock
2. shape of the rock
3. how the rock is formed
4. who discovered the rock
that is it
Answer:
2.1x10⁹ years
Explanation:
U-238 is a radioactive substance, which decays in radioactive particles. It means that this substance will lose mass, and will form another compound, the Pb-206.
The time need for a compound loses half of its mass is called half-life, and knowing the initial mass (mi) and the final mass (m) the number of half-lives passed (n) can be found by:
m = mi/2ⁿ
The mass of Pb-206 will be the mass that was lost by U-238, so it will be mi - m. Thus, the mass ration can be expressed as:
(mi-m)/m = 0.337/1
mi - m = 0.337m
mi = 1.337m
Substituing mi in the expression of half-life:
m = 1.337m/2ⁿ
2ⁿ = 1.337m/m
2ⁿ = 1.337
ln(2ⁿ) = ln(1.337)
n*ln(2) = ln(1.337)
n = ln(1.337)/ln2
n = 0.4190
The time passed (t), or the age of the sample, is the half-life time multiplied by n:
t = 4.5x10⁹ * 0.4190
t = 1.88x10⁹ ≅ 2.1x10⁹ years
i can think of 3 subatomic particles found in a nucleus protons, neutrons, and electrons