AP Chemistry MCQ Unit 1-2

Front

What are isotopes?

Back

Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons, resulting in different atomic masses.

Front

What is sp3 hybridization?

Back

sp3 hybridization occurs when one s orbital and three p orbitals mix to form four equivalent hybrid orbitals, typically found in tetrahedral geometries with bond angles of approximately 109.5°.

Front

How do you calculate the molar mass of a compound?

Back

To calculate the molar mass, sum the atomic masses of all atoms in the molecular formula. For example, C5H9Cl2N3O2 has a molar mass of 214.05 g/mol.

Front

What is an alloy?

Back

An alloy is a mixture of two or more elements, where at least one is a metal, designed to enhance certain properties such as strength, ductility, or corrosion resistance.

Front

What does a photoelectron spectrum indicate?

Back

A photoelectron spectrum provides information about the energy levels of electrons in an atom, helping to determine the electronic structure and the number of electrons.

Front

What is the significance of bond angles in molecular geometry?

Back

Bond angles are crucial for determining the shape of a molecule, which affects its reactivity, polarity, and interactions with other molecules.

Front

What is the difference between a neutral atom and an ion?

Back

A neutral atom has an equal number of protons and electrons, while an ion has a different number of protons and electrons, resulting in a net charge.

Front

How do you determine the number of hydrogen atoms in a given mass of a compound?

Back

To find the number of hydrogen atoms, first calculate the number of moles of the compound using its molar mass, then multiply by the number of hydrogen atoms per molecule.

Front

What is the role of carbon in steel production?

Back

Carbon is added to iron to create steel, enhancing its strength and hardness while maintaining ductility.

Front

What is the charge of common ions formed by elements?

Back

Elements tend to form ions with charges based on their group in the periodic table; for example, Group 1 elements typically form +1 ions, while Group 3 elements often form +3 ions.