Which of the following is a characteristic of robust scientific knowledge?
It is frequently re-examined.
It develops over a short duration of time.
It has been disproven several times.
It is rarely subjected to arguments.
Which of the following provides evidence to support Bohr's theory of atomic orbitals?
Plum Pudding Model
Gold foil experiment
Radiation produced when beryllium is bombarded with alpha particles
Spectrum of colors emitted by gas.
Which of the following observations indicates that an atom has neutrons?
Some uncharged particles bounce back from gold foil when it is bombarded with alpha particles.
Some uncharged particles are scattered by a beryllium atom when it hits gold foil.
A radiation with neutral particles is emitted when alpha particles strike beryllium atoms.
A radiation which attracts electrons is produced when a beryllium atom is bombarded with alpha particles.
The table shows the charge on three unknown subatomic particles. Which particle is most likely present in the nucleus of an atom?
Only particle C
Only particle A
Both particles B and C
Both particles A and B
The table shows the number of charged subatomic particles in an ion. A negatively charged substance is brought near the ion. What will most likely happen and why?
The ion will repel the substance because it has more protons than electrons.
The ion will repel the substance because it has more electrons than protons.
The ion will attract the substance because it has more protons than electrons.
The ion will attract the substance because it has more electrons than protons.
What is the highest point of a wave called?
Trough
Frequency
Crest
Amplitude
A football player experiences acute pain in his knee. Which of the following methods can a doctor use to diagnose the reason for the pain?
Use x-ray radiation to see if there are any fractured bones
Use radio waves emitted by radioactive substances to look at bones
Use infrared radiation from warm objects to look inside the knees
Use radiations emitted by very hot objects to penetrate the skin and bones.
What term is used to describe the lowest energy level of a particle?
Excited state
Ground state
Photon
Emission spectrum
An electron moved from a lower energy level to a higher energy level. What most likely happened during the transition?
A random amount of light was released.
A random amount of light was absorbed.
A fixed amount of energy was released.
A fixed amount of energy was absorbed.
This is represented by the letter n. n is the first number that describes the probable position of every electron and can be any whole number from 1 to 7.
Principle atomic number
Principle quantum number
Principle electron number
Principle ionic number
The table compares the number of electrons in two unknown neutral atoms. Use this information to determine the number of valence electrons in the atoms. Which of the following correctly compares the stability of the two atoms?
Both are highly reactive.
Both are unreactive.
A is unreactive and D is reactive.
D is unreactive and A is reactive.
A substance is present in the gaseous state at room temperature. Which of the following best explains the probable position of the substance in the periodic table?
It is between groups 1 to 12 because it is a metal.
It is between groups 1 to 12 because it is a nonmetal.
It is between groups 13 to 18 because it is a metal.
It is between groups 13 to 18 because it is a nonmetal.
Which of the following groups of elements are likely to have substances that are both metallic and non-metallic properties?
Group 18
Lanthanides
Group 14
Actinides
This group of elements is silvery and shiny. They are extremely reactive because they lose their outer electron easily to form a cation. Because of this, they cannot exist alone in nature.
Alkaline metals
Alkali metals
Transition metals
Metalloids
Which of the following properties increase down a column in the periodic table?
Ionic radii
Effective nuclear charge
Number of valence shell electrons
Ionization energy
Which of the following correctly compares the radii of Cl and Cl−?
Cl has a smaller radius than Cl− because Cl has an expanded electron cloud
Cl has a larger radius than Cl− because Cl− has an additional energy shell.
Cl has a larger radius than Cl− because Cl has an additional energy shell.
Cl has a smaller radius than Cl− because Cl− has an expanded electron cloud.
Which of the following explains how Albert Einstein tried to influence the discovery of the energy equation?
He supported the use of radioactive elements for medical diagnostic purposes.
He opposed the use of nuclear fusion during the Manhattan project.
He recommended applying the principles of nuclear fission to defend against enemies.
He recommended uncontrolled fusion for medical testing and treatment.
Which of the following is true for a reliable scientific source?
It cites opinions.
It cites logic.
It cites valid data.
It cites common sense.