- Basic Math and Science Atomic Structure and Bonding Questions and Answers Flashcards

Which model of the atom describes electrons as existing in a probability cloud or orbital rather than a fixed orbit?

Answer: Quantum mechanical model

The quantum mechanical model uses orbitals — regions of probability — to describe where electrons are likely to be found.

Sodium (Na) has an atomic number of 11. How many electrons are in its outermost shell?

Answer: 1

Sodium's electron configuration is 2-8-1, placing one electron in the third (outermost) shell.

Double covalent bonds involve the sharing of how many electrons between two atoms?

Answer: 4

A double bond consists of two shared pairs of electrons, totaling 4 electrons between the two atoms.

Which of the following pairs would most likely form an ionic compound?

Answer: Sodium and chlorine

Sodium is a metal and chlorine is a nonmetal; large electronegativity differences between metals and nonmetals favor ionic bonding.

An element has 17 protons. It gains one electron to become an ion. What is the charge of this ion?

Answer: -1

Gaining one electron adds a negative charge, making the ion a 1- (chloride) ion.

What does electronegativity measure?

Answer: An atom's ability to attract shared electrons in a chemical bond

Electronegativity quantifies how strongly an atom in a bond pulls the shared electron pair toward itself.

Which of the following molecules contains a triple covalent bond?

Answer: N₂

N₂ has a triple bond (three shared pairs of electrons) between the two nitrogen atoms.