<span>The magnetic field of the Earth serves a useful purpose in deflecting Solar radiation. Without the magnetic field there is much more charged-particle radiation striking the surface. The auroras would occur everywhere instead of at the magnetic poles. Compass needles wouldn't work, and then they would flip direction.. The magnetic field IS DECREASING and could go to zero and reverse sometime in the next few tens-of-thousands of years.</span>
7=cells
9= The Central Nervous system
10= not sure
The by-product of the chlorination of an alkane is <u>HCl</u>
Explanation:
- Chlorination is the process of adding chlorine to drinking water to disinfect it and kill germs. Different processes can be used to achieve safe levels of chlorine in drinking water.
- Chlorination of alkane gives a mixture of different products.
- When consider mechanism of alkanes chlorination, free radicals are formed during the reaction to keep the continuous reaction.
- Different alkyl chloride compounds, extended carbon chains compounds and HCl are formed as products in product mixture.
- Chlorination byproducts, their toxicodynamics and removal from drinking water.
- Halogenated trihalomethanes (THMs) and haloacetic acids (HAAs) are two major classes of disinfection byproducts (DBPs) commonly found in waters disinfected with chlorine
- Chlorine is available as compressed elemental gas, sodium hypochlorite solution (NaOCl) or solid calcium hypochlorite (Ca(OCl)2
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.
