Lesson 3 (PRELIMS)

Question 1

Anything that occupies space and mass. All matters was composed of small indivisible pieces which is called atom.

Answer 1

Matter

Question 2

Is the smallest particle of a chemical compound that retains of all the chemical characteristics of that compound.

Answer 2

Molecule

Question 3

_____ can have as few as two atoms or many hundreds of atoms; therefore tens of thousands of different chemical compounds can be created by changing the number of atoms or configuration of atom within the molecule.

Answer 3

Molecules

Question 3

Every single object is composed of atoms. Even our body is made up of many, many individual atoms. There are over _____ different types of atom. These different types are called _____.

Answer 3

100
elements

Question 4

Under normal conditions, many elements (atoms) may stick together to form larger, different stuff. This joining of different atoms is called a _____ or _____. An example of compound is water, in which the two groups of hydrogen and one oxygen atom fused together forming (H2O) the matter called water.

Answer 4

compound or molecules

Question 5

Atom presented by many symbols: the ancient Greeks envisioned four different atoms, representing air, fire, earth and water. These symbols were adopted by medieval alchemist.

Answer 5

Medieval Atom

Question 6

Atom presented by many symbols: his description of atom is like a pair of hook and eye to account for chemical combination.

Answer 6

Dalton’s Atom

Question 7

Atom presented by many symbols: his description is like plum pudding, with the plums representing the electrons.

Answer 7

Thompson’s Atom

Question 8

Atom presented by many symbols: his description of atom is a small, dense, positively charged nucleus surrounded by electrons in precise energy levels.

Answer 8

Bohr’s Atom

Question 8

History of atom: atomos (indivisible); theory of the universe; you could not divide it anymore

Answer 8

Democritus 400 BC

Question 9

History of atom: first to adopt democritus theory; indestructable and unchangeable

Answer 9

John Dalton - 1800s

Question 10

History of atom: electron, plum pudding

Answer 10

J. J. Thomson - 1890s

Question 10

History of atom: Gold fail experiment; termed nucleus

Answer 10

Ernest Rutherford - 1910s

Question 11

History of atom: Planet model

Answer 11

Niels Bohr - 1910

Question 12

History of atom: atomic model until today

Answer 12

Erwin Schrodinger - 1920

Question 12

At present, the _____ (1913) description of an atom is currently used. Model was a miniature of a solar system in which the electrons revolve about the nucleus in prescribed orbits or energy level.

Answer 12

Niels Bohr

Question 13

Atom has a central core called the _____ where most of its atomic mass is located, and a surrounding clouds of electrons in a shell orbit around the nucleus (radius of electronic orbits, _____ m).

Answer 13

nucleus
10^-10

Question 14

The properties of an atom are derived from the constitution together with the _____ and organization of the _____.

Answer 14

number
orbital electrons

Question 14

There are three fundamental blocks in the atomic structure, the _____, _____ and _____.

Answer 14

Electron, proton and the neutron

Question 14

• Tiny and very light particles
• Have a negative electrical charge (-)
• Move around outside the nucleus

Answer 14

a. Electrons

Question 15

• Much larger and heavier than electrons
• Have a positive electrical charge (+)
• Located in the nucleus of an atom

Answer 15

b. Protons

Question 15

• Large and heavy like protons
• Have no electrical charge (neutral)
• Located in the nucleus of an atom

Answer 15

c. Neutrons

Question 16

• Indicates the number of protons in the nucleu
• In a neutral atom, the number of protons is equal to the number of electrons
• To get the atomic number: (2 = A - N)
  ● Atomic mass no. minus the number of neutrons

Answer 16

a. Atomic Number ( Z )

Question 17

• It is the number of protons and neutrons in the nucleus
• To get the atomic mass number: (A = Z + N)
  ● Atomic No. plus the number of neutrons

Answer 17

b. Atomic Mass Number ( A )

Question 17

- To get the number of neutrons: (N = A - Z) ● Atomic Mass No. minus Atomic No.

Answer 17

c. Neutron ( N )

Question 17

- An _____ is the way in which electrons are arranged in an atom. Electrons are arranged in _____ around an atom's nucleus.

Answer 17

electron arrangement shells

Question 17

- A _____ is the pathway followed by electrons around an atom's nucleus. These are also called _____ since these shells are arranged around the nucleus according to the energy that an electron in that shell is composed of.

Answer 17

shell energy levels

Question 18

- The presence of these _____ indicates that the energy of an atom is quantized. In other words, there are discrete energy values for the electrons that are in the movement Particle Relative around the nucleus.

Answer 18

shells

Question 18

- In order to recognize these shells, they are named as K, L, M, N, O, etc. The shell in the lowest energy level is ___ shell.

Answer 18

K

Question 19

- But scientists have named these shells using _____. Each and every shell has its own quantum number. The quantum number given for the shells is named as the principal quantum number. Then the shell at the lowest energy level is n=___.

Answer 19

quantum numbers 1

Question 20

- All shells do not hold the same number of electrons. The lowest energy level can only hold a maximum of 2 electrons. The next energy level can hold up to 8 electrons. There is a pattern of the number of electrons that a shell can hold.. It is called _____Formula - a formula used to determine the maximum number of electrons per shell or orbit. This pattern is given below using the ___ formula or notation.

Answer 20

Pauli Exclusion 2n^2

Question 21

- The maximum number of electrons that can exists in each shell increases with the distance in each shell in the nucleus. However, the maximum number of electrons that any shell can hold is ___. No shell can have more than this electrons. Higher shells can hold more electrons than that of lower shells.

Answer 21

32

Question 22

- The _____ is the minimum energy that is required to remove an electron from an atom, as the negatively charged electrons are held in place by the electrostatic pull of the positively charged nucleus. The electron binding energy is measured in _____, where 1 eV = _____.

Answer 22

electron binding energy electron volt (eV) 1.6 x 10-19 Joules.

Question 23

An _____ is the amount of kinetic energy gains when accelerated through a potential difference of one volt. The conversion to Sl units is 1 ___ = 1.6 x 10-19 joules.

Answer 23

electron volt (eV)

Question 24

- An eV is a very small unit of energy, so in many applications, it is more common to use kiloelectronvolts ( 1 keV = 1000 eV ) or mega electron volts ( 1 MeV = 1,000,000 eV ). Magnitude of the electron binding energy is: ● _____ proportional to the atomic number ( Z ) The higher the atomic number, the higher the electron binding energy. ● _____ proportional to the distance from the nucleus Inner-shell electrons will have greater binding energy than outer-shell electrons.

Answer 24

Directly Indirectly

Question 25

- An electron can only be removed from an atom if the applied energy is _____ than its electron binding energy. When an inner-shell electron is ejected, the Vacancy will be filled by an electron from an outer shell. The excess energy from this shift is emitted as electromagnetic radiation.

Answer 25

greater

Question 25

In physics, _____ is the emission or transmission of energy in the form of waves or particles through space or through a material medium.

Answer 25

radiation

Question 26

- Radiation can either _____ or _____, depending on its energy and ability to penetrate matter.

Answer 26

ionizing or non-ionizing

Question 26

- _____ is the process resulting in the removal of an electron from an atom, leaving the atom with a net positive charge.

Answer 26

lonization

Question 27

- Radiation emission as the result of an interaction, on the other hand, depends on both the incoming particle and the material it hits, and that is theoretically predictable if enough information is known. It can be produced in one of two ways: ● By the _____ of a particle with matter ● By _____ of an unstable atom (radionuclide).

Answer 27

interaction radioactive decay

Question 28

- Each individual arrangement of protons and neutrons is referred to as a _____. According to its atomic mass, atomic number and the nuclear energy state of a ____, we can characterize the following categories of nuclides:

Answer 28

nuclide

Question 29

- Nuclides which have the same number of protons.

Answer 29

a. Isotopes

Question 29

- Atoms of different elements which contain the same number of neutrons with different atomic mass number and atomic number.

Answer 29

b. Isotones

Question 30

- Atoms of different elements which have the same atomic mass number but different atomic number.

Answer 30

c. Isobar

Question 31

- Atoms of the same atomic number and the same mass number but different energy states.

Answer 31

d. Isomer

Question 32

- Radiation is described by its type and energy. - The type of radiation fall into two main categories: i. _____ - Consists of photons that have energy, but no mass or charge. A photon, as described by quantum theory, is a "particle" or "quantum" that contains a discrete quantity of electromagnetic energy which travels at the speed of light, 3 x 103 meters per second. A photon is sometimes described as a "packet of light". Visible light, UV light, xrays and gamma rays are all photons. h. ii. _____ Consists of particles that have mass and energy and may or may not have an electric charge. Example of particulate radiation include alpha particles, protons, beta particles, and neutrons.

Answer 32

Electromagnetic Radiation Particulate Radiation

Question 33

- Similar radiation may be produced _____in particle accelerators or x-ray generators. The naming is complicated as the radiation is often named according to its source, even when identical to similar radiation coming from other sources. - For example, high-energy electromagnetic radiation (photons) coming from the atomic electrons are called _____ whereas similar photons coming from inside the nucleus are called ______.

Answer 33

artificially x-rays gamma-rays