Describe how the size and growth rate of the human population has changed in the last 200 years?

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.

the awnser is group 12

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock