Chemistry- Atomic Structure Unit Test Study Guide (Ch. 4 & 5)

Atomic Structure Unit Test Study Guide (Ch. 4 & 5)

Test September 29, 2023

Multiple Choice

smallest particle of an element that retains its identity in a Chemical reaction

• Atom

• Proton

• Neutron

In the early 1800s, the english chemist John Dalton performed a number of experiments that eventually led to the acceptance of the idea of atoms. He formulated the first atomic theory since the "death of chemistry" that occurred during the prior 2000 years. Dalton theorized that all matter is made of atoms and that atoms are too small to see, "uncuttable" , and indestructible. He also theorized that all atoms of a given element are exactly alike and atoms of different elements are different.

Dalton’s atomic theory

Democritus, a philosopher in ancient Greece, began the search for a description of matter. He questioned whether matter could be divided into smaller and smaller pieces forever until eventually the smallest possible piece would be obtained. He believed that the smallest possible piece of matter was indivisible and he named the smallest piece of matter "atomos", meaning "not to be cut". To Democritus, atoms were small, hard particles that were all made of the same material, but were formed into different shapes and sizes.

Democritus’ idea of the atom.

Dalton's Atomic theory

​Dalton’s atomic theory.

1. All elements are composed of tiny indivisible particles called atoms

2. Atoms of the same element are identical. The atoms of any of element are different from those of any other element.

3. Atoms of different elements can physically mix together or can chemically combine in simple whole-number ratios to form compounds.

4. Chemical reactions occur when atoms are separated from each other, joined, or rearranged in a different combination. Atoms of one element, however, are never changed into atoms of another element as a result of a chemical reaction. 

Explain how scientists observe individual atoms.

Atoms are very small. If you could line up 100,000,000 copper atoms side by side, they would produce a line only 1 cm long!

Despite their small size, individual atoms are observable with instruments such as scanning electron microscopes.

Multiple Choice

Atoms are very small. If you could line up 100,000,000 copper atoms side by side, they would produce a line only 1 cm long!

Despite their small size, individual atoms are observable with instruments such as scanning electron microscopes.

• Individual atoms are observable with instruments such as scanning electron microscopes.

• Individual atoms are observable with music instruments

• Individual atoms are observable with instruments such as scanning printers.

• Individual protons are observable with instruments such as scanning electron microscopes.

Multiple Choice

negatively charged subatomic particles, mass is 1/1840 the mass of a hydrogen atom, live on the outside “shells” of atoms, symbol e-

• Proton

• Electron

• Neutron

Multiple Choice

positively charged subatomic particles, mass 1840 times that of an electron, live in the nucleus of atoms, symbol p+

• Electrons

• Neutrons

• Protons

Multiple Choice

subatomic particle with no charge, mass equal to proton, live in nucleus of atom, symbol n0

• Protons

• Neutrons

• Electrons

Multiple Choice

tiny central core of an atom and is composed of protons and neutrons.

• Protons

• Nucleus

• Electrons

In the nuclear atom, the protons and neutrons are located in the positively charged nucleus. The electrons are distributed around the nucleus and occupy almost all the volume of the atom.

They exist in...

Three kinds of subatomic particles are electrons, protons, and neutrons.

Three Subatomic Particles:

List and describe the three subatomic particles. Include where each particle exists in an atom, their charges, and their mass.

Multiple Choice

Where are protons and neutrons Located?

• are located in the positively charged nucleus.

• are located in the negative charged nucleus.

Multiple Choice

Where are the electrons located?

• The electrons are distributed around the nucleus and occupy almost all the volume of the atom.

• The electrons are distributed around the electrons and occupy almost all the volume of the space.

Explain the plum pudding model and compare it to Bohr’s atomic model.

​This answer choice is referring to Bohr's model of the atom, where electrons occupy fixed energy orbits around the nucleus. So as we discussed before, the plum pudding model is different from the hard-sphere model of the atom because the plum pudding model included negatively charged particles known as electrons.

Multiple Choice

is the number of protons in the nucleus of an atom of that element.

• atomic number

• mass number

• atomic mass

Multiple Choice

The total number of protons and neutrons in an atom is called the.....

• Mass quantity

• atomic number

• Mass number

Multiple Choice

are atoms that have the same number of protons but different numbers of neutrons.

• Isotope

• atomic number

• atomic mass

Multiple Choice

______ is defined as 1/12th of the mass of a carbon-12 atom.

• atomic mass unit (amu)

• atomic mass

• mass quanitty

Multiple Choice

a weighted average mass of the atoms in a naturally occurring sample of the element.

• atomic quantity

• atomic mass

Explain why each element differs?

Isotopes

Because isotopes of an element have different numbers of neutrons, they also have different mass numbers.

Despite these differences, isotopes are chemically alike because they have identical numbers of protons and electrons, which are the subatomic particles responsible for chemical behavior.

What makes one element different from another?

Elements are different because they contain different numbers of protons. 

An element’s atomic number is the number of protons in the nucleus of an atom of that element. 

Since all hydrogen atoms have one proton, the atomic number of hydrogen is 1. 

Remember that atoms are electrically neutral. Thus, the number of electrons must equal the number of protons. 

Multiple Select

How many protons, electrons, and neutrons are in each atom?

(Carbon (C) (atomic #6) > mass = C: 12.011

• Protons = 6

• Electrons = 6

• Neutrons = 6

• Protons = 12

Multiple Choice

The fixed energies an electron can have are called ...

• Energy Levels

• quantum

• Energy

Multiple Choice

A .... of energy is the amount of energy required to move an electron from one energy level to another energy level.

• atomic mass

• quantum

• quantum mechanical model

Multiple Choice

The ...................................................determines the allowed energies an electron can have and how likely it is to find the electron in various locations around the nucleus of an atom.

• quantum mechanical model

• guantaum level

• atomic mass

Multiple Choice

....is the probability of finding an electron at various locations around the nucleus.

• atomic unit

• atomic mass

• atomic orbital

In 1913, Niels Bohr developed a new atomic model

Bohr proposed that an electron is found only in specific circular paths, or orbits, around the nucleus.

Explain how energy is affected by the energy level.

The amount of energy an electron gains or loses in an atom is not always the same. Like the rungs of the strange ladder, the energy levels are not equally spaced. 

The higher level are closer together. The higher the energy level occupied by an electron, the less energy it takes to move from that energy level to the next higher energy level.

 How do scientists use the electron cloud to determine the location of electrons?

In the quantum mechanical model of the atom, the probability of finding an electron within a certain volume of space surrounding the nucleus can be represented as a fuzzy cloudlike region. Where the cloud is more dense, the probability of finding an electron is high.

Atomic Orbitals - S, P, D, F

Different atomic orbitals are denoted with letters. S orbitals are spherical and p orbitals are dumbbell-shaped.

Multiple Choice

The ways in which electrons are arranged in various orbitals around the nuclei of atoms are called ______

• electron configurations

• electron connection

Multiple Choice

What's the max orbitals of S ?

• 2 max

• 6 max

• 1 max

• 3 max

Multiple Choice

What's the max orbitals of P ?

• 7 max

• 6 max

• 6.5 max

• 4 max

Multiple Choice

What's the max orbitals of D ?

• 10 max

• 9 max

• 11 max

• 5 max

Multiple Choice

What's the max orbitals of F ?

• 10 max

• 13 max

• 7 max

• 14 max

Multiple Choice

• height of a wave; distance from midline to top of wave

• amplitude

• height

• length

• distance

Multiple Choice

• distance from crest to crest;

                                     measured in nanometers

    (1 meter = 1 x 109 nm)

• Wavelength (λ)

• measuring tape

• height/distance

Multiple Choice

• number of waves per second; 

      measured in Hertz  (1 Hz = 1/sec)

• Accuracy

• Frequency (ν)

Multiple Choice

Electrons in atoms will absorb and emit energy in the form of ____________ (waves/photons).

• electromagnetic radiation

• electromagnetic ration

• electromagnetic distance

Multiple Choice

a band of colors, as seen in a rainbow, produced by separation of the components of light by their different degrees of refraction according to wavelength.

• distance

• spectrum

• Saturn

Multiple Choice

Each spectral line in an atomic emission spectrum of an element corresponds exactly to one wavelength of light emitted by the electrons of that element.

*no two elements have the same ___________.

• 1. atomic emission spectrum

• spectrum

• addition postulate

Describe what happens to atoms when they gain or lose energy.

When an electric current is passed through a gaseous element, the electrons of the atoms are energized. This energy causes them to emit light. 

When atoms absorb energy, their electrons move to higher energy levels. These electrons lose energy by emitting light when they return to lower energy levels.