I believe deforestation increases the biodiversity of a forest ecosystem. Trees are an essential organism for all ecosystem and forms of life. Without trees we have no oxygen, however trees so reproduce, but when you are chopping them down at the rate of deforestation(hence how it got it's name) then there is an issue
Answer:
The upper and lower limits for the room-temperature thermal conductivity of a magnesium oxide material having a volume fraction of 0.10 of pores that are filled with still air are
Ku = 38.252 W/mK
K lower = 0.199 W/mK
Explanation:
As we know
Ku = Vp * Kair + Vmagnesium * K metal
Ku = 0.10 *0.02 + (1-0.25) * 51
Ku = 38.252 W/mK
The lower limit
K lower = Kmetal* Kair/( Vp * Kmetal + Vmetal * K air)
K lower = (0.02*51)/(0.10*51 + 0.90 * 0.02)
K lower = 0.199 W/mK
Adopting the number of avogrado 6.02 * 10²³ / mol
<span>Sodium chloride (table salt)</span> Molar Mass = 58.44 g / mol
We will first have to find the number of moles in 35 grams of the element, like this:
1 mol ----------------- 58.44 g
X ---------------------- 35 g
58.44 * x = 35 * 1
58.44x = 35
X = 0.598904...
X ≈ 0.60<span> mol </span>
Now we will find how many atoms there are in 0.60 mol of this element, like this:
1 mol -------------------- 6.02 * 10²³ atoms
0.60 mol ----------------- X
X = 0.60 * 6.02 * 10²³
Answer:
The possible valances can be determined by electron configuration and electron negativity
Good Luck even though this was asked 2 weeks ago
Explanation:
All atoms strive for stability. The optima electron configuration is the electron configuration of the VIII A family or inert gases.
Look at the electron configuration of the nonmetal and how many more electrons the nonmetal needs to achieve the stable electron configuration of the inert gases. Non metals tend to be negative in nature and gain electrons. ( They are oxidizing agents)
For example Florine atomic number 9 needs one more electron to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Flowrine has a valance of -1
Oxygen atomic number 8 needs two more electrons to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Oxygen has a valance charge of -2.
Non metals with a low electron negativity will lose electrons when reacting with another non metal that has a higher electron negativity. When the non metal forms an ion it is necessary to look at the electron structure to determine how many electrons the element can lose to gain stability.
For example Chlorine which is normally -1 like Florine when it combines with oxygen can be +1, +3, + 5 or +7. It can lose its one unpaired electron, or combinations of the unpaired electron and sets of the three pairs of electrons.
I think the correct answer from the choices listed above is option C. Chemical reaction is the process <span>that changes one set of chemicals into another set of chemicals. In a chemical reaction, old bonds are broken down forming new bonds therefore new </span>substances<span> with new properties.</span>
