Number of neutrons = mass number - atomic number = 40 - 19 = 21 answer
Answer:
The chemical formula is I2F9
Explanation:
This was because the experiment showed that a substance could emit radiation even while it was not exposed to light.
Answer: State
Explanation:
The rock on the left is more shiny than the right, so that’s incorrect.
The rocks are not the same color, so that’s also incorrect.
Even though you can’t feel the textures, the right rock looks grainy and the left on doesn’t.
They both are solid, so that is the correct answer.
