Unit 2

Atomic Theory

100

What part of the atom contains protons and neutrons?

The nucleus

200

Why are all the atomic masses on the periodic table decimals?

They are weighted averages of all the isotopic masses of that element.

300

What did Rutherford discover in his gold foil experiment?

A positively-charged nucleus.

400

How many neutrons are in argon-40

22

500

How many electrons are in a potassium ion?

18

Periodic Trends

100

Who came up with the first periodic table?  

Mendeleev.

200

What effect explains why ionization energy decreases from top to bottom?  

The electron shielding effect.

300

Why are metalloids called metalloids?

They share properties with both metals and nonmetals.

400

Which element has the highest electronegativity?

Fluorine.

500

How many electrons does neon tend to gain or lose?

0

Electromagnetic Spectrum

100

What formula do we use to calculate the energy of a photon?

E = hν

200

What is a quantum?

The smallest amount of energy that can be gained or lost by an atom.

300

What type of light has the least energy?

Radio Waves

400

Why was Bohr’s model incorrect?

1. His model did not account for atoms with more than 1 electron. 2. He didn’t account for electrons having wave-like properties. 3. He didn’t account for 3-D orbitals.

500

What did Schrödinger contribute to the Quantum Mechanical Model of the atom?

He mathematically determined the wave functions needed for de Broglie’s model of wavelike electrons.

Electron Configuartion

100

What is the first sublevel filled in an atom’s electron configuration?

1s

200

Calcium loses two electrons to become an ion; what element is this Ca²⁺ ion isoelectronic with?

Argon

300

What is the highest energy sublevel with electrons in titanium?

3d

400

How many electrons are in all the p orbitals of Arsenic?

15

500

Electron configuration for Po^2-

1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²4f¹⁴5d¹⁰6p⁶

Random

100

Electrons in the same sublevel occupy empty orbitals first before pairing up

What is Hund's Rule?

200

What is states that only two electrons can occupy a single orbital?

What is the Pauli exclusion principle?

300

This scientist proposed that electrons orbit the nucleus in fixed energy levels, leading to a planetary model of the atom.

Niels Bohr

400

This physicist conducted the gold foil experiment, leading to the discovery of the atomic nucleus and the conclusion that an atom is mostly empty space.

Ernest Rutherford

500

What is states that electrons fill orbitals that have the lowest energy first

What is the Aufbau principle?