Answer: A mechanical wave is a disturbance in matter that transfers energy through the matter. A mechanical wave starts when matter is disturbed. A source of energy is needed to disturb matter and start a mechanical wave.
Answer:
Elemental gold to have a Face-centered cubic structure.
Explanation:
From the information given:
Radius of gold = 144 pm
Its density = 19.32 g/cm³
Assuming the structure is a face-centered cubic structure, we can determine the density of the crystal by using the following:


a = 407 pm
In a unit cell, Volume (V) = a³
V = (407 pm)³
V = 6.74 × 10⁷ pm³
V = 6.74 × 10⁻²³ cm³
Recall that:
Net no. of an atom in an FCC unit cell = 4
Thus;


density d = 19.41 g/cm³
Similarly; For a body-centered cubic structure

where;
r = 144


a = 332.56 pm
In a unit cell, Volume V = a³
V = (332.56 pm)³
V = 3.68 × 10⁷ pm³
V 3.68 × 10⁻²³ cm³
Recall that:
Net no. of atoms in BCC cell = 2
∴


density =17.78 g/cm³
From the two calculate densities, we will realize that the density in the face-centered cubic structure is closer to the given density.
This makes the elemental gold to have a Face-centered cubic structure.
Answer:
gravity equation.
Explanation:
use this gravity equation
F= G(m1*m2/d²)
From the calculation, the standard free energy of the system is -359kJ.
<h3>What is the standard free-energy?</h3>
The standard free-energy is the energy present in the system. We have to first obtain the cell potential using the formula;
Ereduction - E oxidation = 0.96 V - 0.34 V = 0.62 V
Using the formula;
ΔG = -nFEcell
ΔG =-(6 * 96500 * 0.62)
ΔG =-359kJ
Learn more about free energy:brainly.com/question/15319033
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2.43*1000.
There are 1000 grams in a kilogram