What do elements in the same family generally have similar properties?
1 answer:
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Answer:
- It is 3.
Explanation:
The model written correctly is:
This is a mathematical question, instead of a chemistry question, and you should use calculus to find the nitrogen level that gives the best yield, since this is an optimization problem.
The best yield is the maximum yield, and the maximum, provided that it exists, is found using the first derivative and making it equal to zero: Y' = 0
To find Y' you must use the quotient rule.
Now make Y' = 0
- The denominator is never equal to zero, because it is always positive and greater than 9.
- Make the numerator equal to zero:
9k - kN² = 0
- Factor: k (9 - N²) = 0
- Since k is a positve constant, it is not equal to zero, and the other factor, 9 - N², must be equal to zero:
9 - N² = 0 ⇒ (3 - N) (3 + N) = 0
⇒ 3 - N = 0 or 3 + N = 0 ⇒ N = 3 or N = -3.
Since N is nitrogen level, it cannot be negative and the only valid answer is N = 3.
You can prove that it is a maximum (instead of a minimum) finding the second derivative or testing some points around 3 (e.g. 2.5 and 3.5).
Answer:
Density of unit cell ( rhodium) = 12.279 g/cm³
Explanation:
Given that:
The radius (r) of a rhodium atom = 135 pm
The atomic mass of rhodium = 102.90 amu
For a face-centered cubic unit cell,
where;
a = edge length.
Making "a" the subject of the formula:
a = 381.8 pm
to cm, we get:
a = 381.8 × 10⁻¹⁰ cm
However, recall that:
where;
mass of unit cell = mass of atom × numbers of atoms per unit cell
Also;
Recall also that number of atoms in a unit cell for a face-centered cubic = 4
So;
mass of unit cell = 6.83380375 × 10⁻²² g
Density of unit cell ( rhodium) = 12.279 g/cm³