Answer:
C
Explanation:
For A, 2Al(OH)3 contains 6H on the left side of the equation but only has 3H on the right side of the equation, thus its not balanced
For B, there is 2(Al2), which is 4, on the left side of the equation but only 2Al on the right side of the equation, so it is not balanced.
For D, theres a total of 6 H on the left side of the equation as there is (OH)3 and 3H, but none of the right side, so its not balanced.
C is the correct answer as
on the left side of the equation:
2 Al(OH)3 has 2Al, 6O, and 6H
on the right side of the equation:
Al2O3 has 2Al and 3O
3 H20 has 3H and 6O
this makes a total of 2Al, 6H and 6O, which is equal to the number of each element in the left side, thus it is balanced and is the right answer.
In the future for these type of qns, you want to add up the number of each element on the left, then the ride, and see compare the numver of element they have. if the number of all the elements on both sides are the same, the equation is balanced.
Answer:
a) octahedral electron domain geometry
b)square planar molecular geometry
c) a bond angle of 90°
Explanation:
According to the Valence Shell Electron Pair repulsion Theory, the shape of a molecule is dependent on the number of electron pairs on the valence shell of the central atom in the molecule. These electron pairs orient themselves as far apart in space as possible to minimize electron pair repulsion.
Electron pairs may be lone pairs or bond pairs. Lone pairs of electrons cause more repulsion than bond pairs. These lone pairs often cause the molecular geometry to depart from what is predicted on the basis of the electron domain geometry due to greater repulsion of lone pairs.
When a molecule has six electron domains consisting of four bond pairs and two lone pairs, the bonding pairs arrange themselves at the corners of a square at a bond angle of 90° with the lone pairs found above and below the plane of the bonding groups leading to a square planar molecular geometry
<u>Answer:</u> The correct answer is Option C.
<u>Explanation:</u>
To calculate the number of moles, we use the equation:
Given mass of methane = 48.2 g
Molar mass of methane = 16 g/mol
Putting values in above equation, we get:
According to mole concept:
1 mole of compound contains 
number of molecules.
So, 3.0125 moles of methane will contain = 
number of molecules.
Hence, the correct answer is Option C.
Density = mass/volume
density = 81 grams/0.9 cubic centimetersdensity = 90 grams per cubic centimeter
The density of the sample is 90 grams per cubic centimeter.
