Question

fill in the missing information:
| symbol | atom or ion?
check all that apply | number of
protons | number of
electrons |

	neutral atom cation anion	35	36
	neutral atom cation anion	12	10
	neutral atom cation anion	41	41

Explanation:

Step 1: Recall atomic structure rules

• The number of protons is the atomic number (Z), which determines the element.
• For a neutral atom: number of protons = number of electrons.
• For a cation: number of protons > number of electrons (lost electrons).
• For an anion: number of protons < number of electrons (gained electrons).

Step 2: Analyze the first row

• Protons = 35, Electrons = 36. Since protons < electrons, it's an anion. The element with atomic number 35 is bromine (Br). So the symbol is $\ce{Br^-}$, and check "anion".

Step 3: Analyze the second row

• Protons = 12, Electrons = 10. Since protons > electrons, it's a cation. The element with atomic number 12 is magnesium (Mg). So the symbol is $\ce{Mg^{2+}}$, and check "cation".

Step 4: Analyze the third row

• Protons = 41, Electrons = 41. Since protons = electrons, it's a neutral atom. The element with atomic number 41 is niobium (Nb). So the symbol is $\ce{Nb}$, and check "neutral atom".

Answer:

symbol	atom or ion? (check all that apply)	number of protons	number of electrons
$\boldsymbol{\ce{Mg^{2+}}}$	$\square$ neutral atom $\boldsymbol{\square}$ cation $\square$ anion	12	10
$\boldsymbol{\ce{Nb}}$	$\boldsymbol{\square}$ neutral atom $\square$ cation $\square$ anion	41	41