The
Earth is composed of four different layers. Many geologists believe
that as the Earth cooled the heavier, denser materials sank to the
center and the lighter materials rose to the top. Because of this, the
crust is made of the lightest materials (rock- basalts and granites) and
the core consists of heavy metals (nickel and iron).
<span>The crust is the layer that you live on, and it is the most widely studied and understood. The mantle
is much hotter and has the ability to flow. The Outer and Inner Cores
are hotter still with pressures so great that you would be squeezed into
a ball smaller than a marble if you were able to go to the center of
the Earth!!!!!!</span>
I believe the answer is A. However, I would double check the formula.
Answer:
The given statement - The main criterion for sigma bond formation is that the two bonded atoms have valence orbitals with lobes that point directly at each other along the line between the two nuclei , is <u>True.</u>
Explanation:
The above statement is correct , because the sigma bond is produced by the head on overlapping, the orbitals should all point in the same direction.
<u>SIGMA BONDS -</u> Sigma bonds (bonds) are the strongest type of covalent chemical bond in chemistry. They're made up of atomic orbitals that collide head-on. For diatomic molecules, sigma bonding is best characterized using the language and tools of symmetry groups.
Head-on overlapping of atomic orbitals produces sigma bonds. The concept of sigma bonding is expanded to include bonding interactions where a single lobe of one orbital overlaps with a single lobe of another. Propane, for example, is made up of ten sigma bonds, one for each of the two CC bonds and one for each of the eight CH bonds.
Hence , the answer is true .
Correct answer is C
Na2O + H2O ----> 2 NaOH
:-) ;-)