Answer:
See explanation and image attached
Explanation:
"A formal charge (FC) is the charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity" (chemlibretext).
We can obtain the formal charge from the formula;
Formal Charge = [number of valence electrons on atom] – [non-bonded electrons + 1/2number of bonds].
A structure in which SO2 has a zero formal charge is attached to this answer.
Image credit: Chemtopper
Answer:
b melting
Explanation:
The phase change the substance is undergoing is from solid to liquid and this is called melting.
- To understand this process, we need to know the the substance changing.
- A substance that contains particles that are not easily compressed and packed is a solid.
- Solids have fixed shapes and volumes.
- Liquids can easily flow although they cannot also be easily compressed.
The phase change from solid to liquid is facilitated by a melting process.
1) moles = mass/mR
CaCO3 Mr = 40 + 12 + (16×3)
= 52 + 48
= 100
mass = 15
so the moles would be 15 ÷ 100
which is 0.15 moles of CaCO3
2) moles = mass ÷ Mr
Mr of Al2O3 = 27 + (16×3)
= 27 + 48
= 75
mass = 204
so the moles would be 204/75 which is 2.72 moles of Al2O3