Which of the following is not true about ions? (1 point)
cations are positively charged ions.
anions are common among nonmetals.
charges for ions are written as numbers followed by a plus or minus sign.
when a cation forms, more electrons are transferred to it.

When a cation forms, more electrons are transferred to it

Explanation:

Ions can either be cations (positively charged species) or anions (negatively charged species).

Cations are produced when atoms, typically metal atoms, lose their valence electrons to become positively charged.

Anions are produced when nonmetal atoms gain electrons to become negatively charged.

These definitions already eliminate the majority of choices: cations are positively charged ions. Anions are common among nonmetals.

Thinking about nomenclature, charges are represented by a superscript of a number with either a plus (for positive charges) or a minus (for negative charges).

It is false, however, that when a cation forms, electrons are transferred to it. In reality, cations lose electrons rather than gain.

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.