Number 1 is Comets and asteroids
Number 2 is Comets are made of ice and rock
Number 3 is Meteor
HBr is the formula for hydrobromic acid
Answer:
I don't really understand what you asking in this question so if you don't mind plz tell me in a better form
Answer:
a high school classroom?
Explanation:
a high school classroom prob chemistry
As the atomic radius decreases, it becomes harder to remove an electron that is closer to a more positively charged nucleus. They experience a weaker attraction to the positive charge of the nucleus. Ionization energy increases from left to right in a period and decreases from top to bottom in a group.