3 valence electrons are transferred in the formation of the compound potassium nitride because nitrogen needs 3 valence electron to become stable, or to have the electron configuration of noble Gases.
Cells are surrounded by #2 , Cell membrane and Cell wall thats what protects the cell
Answer:
Both metals and non-metals when burnt in oxygen form their oxides. Oxides of metals are basic in nature and oxides of non-metals are acidic in nature.
Answer:
Heat causes the molecules to move faster (heat energy is converted to kinetic energy), which means that the volume of a solid or a liquid. ... The particles in the air do not have more kinetic energy than particles in the mercury, because they are the same.
Explanation:
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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
