Answer: Homogeneous mixture
Explanation:
Homogeneous mixtures are those mixtures in which the dispersed phase is uniformly distributed throughout the dispersion medium. The dispersed phase has uniform composition throughout the dispersion medium and thus there is no physical boundary between the dispersed phase and the dispersion medium. Example: salt in water
Heterogeneous mixtures are those mixtures in which the dispersed phase is not uniformly distributed throughout the dispersion medium. The dispersed phase does not has uniform composition throughout the dispersion medium and thus there is a distinct physical boundary between the dispersed phase and the dispersion medium. Example: Sand in water
Answer:
valence electrons are the electrons that are located in the outermost electron shell of an element. Knowing how to find the number of valence electrons in a particular atom is an important skill for chemists because this information determines the kinds of chemical bonds that it can form and, therefore, the element's reactivity
Explanation:
You need to show us what you’re talking about first
Answer:
5.8μg
Explanation:
According to the rate or decay law:
N/N₀ = exp(-λt)------------------------------- (1)
Where N = Current quantity, μg
N₀ = Original quantity, μg
λ= Decay constant day⁻¹
t = time in days
Since the half life is 4.5 days, we can calculate the λ from (1) by substituting N/N₀ = 0.5
0.5 = exp (-4.5λ)
ln 0.5 = -4.5λ
-0.6931 = -4.5λ
λ = -0.6931 /-4.5
=0.1540 day⁻¹
Substituting into (1) we have :
N/N₀ = exp(-0.154t)----------------------------- (2)
To receive 5.0 μg of the nuclide with a delivery time of 24 hours or 1 day:
N = 5.0 μg
N₀ = Unknown
t = 1 day
Substituting into (2) we have
[5/N₀] = exp (-0.154 x 1)
5/N₀ = 0.8572
N₀ = 5/0.8572
= 5.8329μg
≈ 5.8μg
The Chemist must order 5.8μg of 47-CaCO3
