Answer:
Weathering involves the use of water and or wind to wear down the environment. The sand dunes were most likely carried by wind to form them and form its shape. Erosion most likely took away parts of the sand to make the sand dune. Deposition most likely deposited sand to the area.
Explanation:
If you possibly want a better explanation, try looking it up :).
#teamtrees #WAP (Water And Plant)
Answer:
Then, at some point, these higher energy electrons give up their "extra" energy in the form of a photon of light, and fall back down to their original energy level.
Explanation:
When properly stimulated, electrons in these materials move from a lower level of energy up to a higher level of energy and occupy a different orbital.
Answer:
0.01395mol Cr2O3
Explanation:
the molar mass of Cr2O3 is 151.9904 g/mol
2.12g Cr2O3 x 1 mol/151.9904g = 0.01395mol Cr2O3
Answer:
a) ammonium ion
b) amide ion
Explanation:
The order of decreasing bond angles of the three nitrogen species; ammonium ion, ammonia and amide ion is NH4+ >NH3> NH2-. Next we need to rationalize this order of decreasing bond angles from the valence shell electron pair repulsion (VSEPR) theory perspective.
First we must realize that all three nitrogen species contain a central sp3 hybridized carbon atom. This means that a tetrahedral geometry is ideally expected. Recall that the presence of lone pairs distorts molecular structures from the expected geometry based on VSEPR theory.
The amide ion contains two lone pairs of electrons. Remember that the presence of lone pairs causes greater repulsion than bond pairs on the outermost shell of the central atom. Hence, the amide ion has the least H-N-H bond angle of about 105°.
The ammonia molecule contains one lone pair, the repulsion caused by one lone pair is definitely bless than that caused by two lone pairs of electrons hence the bond angle of the H-N-H bond in ammonia is 107°.
The ammonium ion contains four bond pairs and no lone pair of electrons on the outermost nitrogen atom. Hence we expect a perfect tetrahedron with bond angle of 109°.
Answer:
Al: 3
S: 6
Explanation:
Al is in Group III. This means that it has 3 valence electrons.
S is in Group VI. This means that it has 6 valence electrons.
I hope this helps :)