Atomic Structures Vocabulary Flashcard

Front

What is the term for the number of protons in the nucleus of an atom?

Back

Atomic Number

Answer explanation

The term for the number of protons in the nucleus of an atom is called the Atomic Number. It uniquely identifies an element and determines its position in the periodic table.

Front

The _______ is the weighted average of the masses of the isotopes of an element.

Back

Average Atomic Mass

Answer explanation

The Average Atomic Mass is the weighted average of the masses of an element's isotopes, reflecting their relative abundances. It differs from the Atomic Number, which counts protons, and the Mass Number, which counts protons and neutrons.

Front

Which scientist is known for the Plum Pudding model of the atom?

Back

J.J Thompson

Answer explanation

J.J. Thompson is known for the Plum Pudding model of the atom, which proposed that atoms are composed of a positively charged 'soup' with negatively charged electrons embedded within it.

Front

The Gold Foil Experiment led to the discovery of the ______.

Back

Nucleus

Answer explanation

The Gold Foil Experiment, conducted by Rutherford, revealed that atoms have a small, dense nucleus at their center, leading to the understanding of atomic structure. Thus, the correct answer is 'Nucleus'.

Front

Bohr's Model is used to represent the ______ of an atom.

Back

Electron configuration

Answer explanation

Bohr’s Model describes the arrangement of electrons around the nucleus, which is known as the electron configuration. It illustrates how electrons occupy different energy levels in an atom.

Front

Back

53

Answer explanation

The atomic number of an element is defined by the number of protons in its nucleus. The symbol \(^{127}_{53}I^{1-}\) indicates iodine (I) with an atomic number of 53, which corresponds to its position in the periodic table.

Front

Back

24

Answer explanation

The mass number of an element is the total number of protons and neutrons in its nucleus. For magnesium, represented as \(^{24}_{12}Mg^{2+}\), the mass number is 24, indicating it has 12 protons and 12 neutrons.

Front

What is the average atomic mass of an element with isotopes: 10 amu (90% abundance) and 11 amu (10% abundance)?

Back

10.1 amu

Answer explanation

To find the average atomic mass, multiply each isotope's mass by its abundance: (10 amu * 0.90) + (11 amu * 0.10) = 9 amu + 1.1 amu = 10.1 amu. Thus, the correct answer is 10.1 amu.

Front

The average atomic mass of an element is calculated by taking into account the abundance of each isotope.

Back

abundance/percentage

Answer explanation

The average atomic mass of an element is determined by the abundance of each isotope, which reflects how common each isotope is in nature. Thus, the correct answer is 'abundance'.

Front

How many protons does He have?

Back

2

Answer explanation

Helium (He) has an atomic number of 2, which means it has 2 protons. This is the defining characteristic of helium, distinguishing it from other elements.