Answer:
Option B, HCO3 1-
Explanation:
The valence of Sodium ion is +1 and the valence of HCO3 is -1. Thus, sodium ion has an extra electron to be donated to complete its outer shell while HCO3 needs an electron to complete its outer shell
Hence Na will combine with HCO3 to form NaHCO3
Option B is correct
Answer:Gases and solids , Solids and liquids
Explanation:
A solid has a definite shape while liquids and gases take the shape of the container in which they are found .
Hence when a substance changes it's state from gas to solid or solid to liquid, it's shape automatically changes as explained above.
Theses can include the power supply circuit a joule meter to measure the energy transferred which makes the calculations a lot easier.