Answer: In the three-dimensional structure of methane, CH₄, the hydrogen atoms attached to a carbon atom are aligned <span>
<u>at the corners of a Tetrahedron</u>.
Explanation: In
Methane (CH</span>₄) the central atom (carbon) is bonded to four hydrogen atoms. So, the central atom is having four electron pairs and all pairs are bonding pairs and lacks any lone pair of electron. According to
Valence Shell Electron Pair Repulsion (VSEPR) Theory the central atom with
four bonding pair electrons and
zero lone pair electrons will attain a
tetrahedral geometry with
bond angles of 109°. Hence, the shape of CH₄ is tetrahedral.
Answer:

Explanation:
From the equation attached ,
is reduced. This is because reduction is equivalent to decrease in the oxidation number. In the equation , The oxidation number of Ni is reduced from +2 to 0.
NB, The oxidation number of a neutral atom is zero
Answer: B, the gas is being squeezed out of the liquid.
Explanation: The gas does not want to be trapped inside of the liquid, so it is trying to force it’s way out. Therefore creating more pressure in the container or whatever the liquid is being held in.
Answer:
The energy for 1 mole of these photons is E = 31 ×
Explanation:
Given data
Wavelength
639.8 ×
m
Plank constant h = 6.626 ×
J sec
Speed of light c = 3 ×
meter per second
We know that Energy of a photon is given by

Value of ( h c ) = 6.626 ×
× 3 ×
= 19.878 × 
639.8 ×
m
Now Energy of a photon

E = 0.031 ×
Joule per mole
E = 31 ×
Therefore the energy for 1 mole of these photons is E = 31 ×
Answer:
Because most solids are denser than water.
Explanation: