Answer:
A
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(Wikipedia).
The formal charge on an atom in a molecule reflects the electron count associated with the atom compared to the isolated neutral atom(University of Calgary).
Looking at all the structures listed A-E for SeO2F2, only structure A minimizes the formal charges for each atom in SeO2F2.
It would keep traveling westward
Answer:
A, Plate boundary movements.
Add-on:
hope this helped at all.
Answer:
Sample A is a pure substance
Sample B is a mixture
Explanation:
We are told that the when the yellow solid, sample A is ground it turned to orange colour and was then dissolved. Some part of the solid settled out at the bottom of the beaker while some part floated on top of the water. 50g of the solid was dissolved and 50.1g of the solid was recovered.
This implies that the substance is pure since the mass dissolved was almost the same mass recovered. The 0.1g addition in mass may result from incomplete drying of the solid.
For sample B, the distillation of the sample of density 0.77 g/ml left a fraction in the beaker with density 1.04 g/ml indicating that the substance is a mixture. Different components of a mixture possess different densities.