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.
Explanation:
a ...15 seconds×(3600 seconds hour)
The answer is mean,mode and median
Answer:
13.5 %
Explanation:
First we<u> calculate the mass of 500 mL of water</u>, using <em>its density</em>:
- 500 mL * 1.00 g/mL = 500 g
Then we <u>calculate the mass percent of potassium sulfate</u>, using the formula:
Mass of Potassium Sulfate / Total Mass * 100%
- 78 g / (78 + 500) g * 100 % = 13.5 %
A combustion reaction of an will generally produce CO2 and H20 -- carbon dioxide and water and/or an oxide
looking at the combustion material C2H2, you know that the end products will be CO2 and H20, so the question is how much of each will you get
well, look at the total amount of carbon atoms, 2 C2, which means a total of 4 carbon atoms in this reaction, since only CO2 has carbon atoms, that means there must be 4 CO2 as an end product and 4 CO2 will use up 4 of 5 O2 molecule leaving only 1 O2 molecule for the H2 reaction.
now O2 has a total of 2 oxygen molecules whereas H20 has only a single oxygen molecule, hence the end product must have 2 H20
check that the H atoms balance out on both sides