Answer:
the packing efficiency is 52.36%
Explanation:
Given the data in the question;
simple cubic unit cell that contains one atom with a metallic radius of 175 pm;
we know that;
Edge length of Simple cubic (a) is related to radius of atom (r) as follows;
a = 2r
since radius r = 175 pm
we substitute
a = 2 × 175 pm
a = 350 pm
Now we get the volume unit;
Volume of unit cell = a³ = ( 350 pm ) = 42875000 pm³
Next we get Volume of sphere;
Volume of Sphere = 
πr³
Volume occupied by 1 atom = × π × ( 175 pm )³
= × π × 5359375 pm³
= 22449297.5 pm³
Now, the packing efficiency = ( Volume occupied by 1 atom / Volume of unit cell ) × 100
we substitute;
packing efficiency = ( 22449297.5 pm³ / 42875000 pm³ ) × 100
= 0.523598 × 100
= 52.36%
Therefore, the packing efficiency is 52.36%
brain stem connects the brain to the rest of the body through spinal cord
Answer:
i dont have a answer im just answering so you can give the person who answered brailiest :)
Explanation:
Answer:
The solution to the given problem is done below.
Explanation:
a)
i) =( 0.002 μg / L )( 1mg / 1000 μg )( 1L / kg )( 1000 mil / 1 billion) = 0.002 ppb
ii) =( 0.002 μg / L )( 1mg / 1000 μg )( 1L / kg )( 1,000,000 mil / 1 trillion) = 2 ppt
iii) =( 0.002 μg / L )( 1 mole / 540g ) = 3.7 x 
μM.
b)
i) =( 0.002 μg / g ) = 0.002 ppm
ii) In solids, ppb = μg/kg
=( 0.002 μg / g )( 1000 mil/ 1 billion) = 2 ppb
As,
CuCO₃ ⇆ Cu²⁺ + CO₃²⁻
So,
Kc = [Cu²⁺] [CO₃²⁻] / CuCO₃
Or,
Kc (CuCO₃) = [Cu²⁺] [CO₃²⁻]
Or,
Ksp = [Cu²⁺] [CO₃²⁻]
As,
Ksp = 1.4 × 10⁻¹⁰
So,
1.4 × 10⁻¹⁰ = [x] [x]
Or,
x² = 1.4 × 10⁻¹⁰
Or,
x = 1.18 × 10⁻⁵ mol/L
To cahnge ito g/L,
x = 1.18 × 10⁻⁵ mol/L × 123.526 g/mol
x = 1.45 × 10⁻³ g/L
