Atomic Theory
What is the definition of an atom?
The smallest unit of an element.
What are the three main types of subatomic particles?
Protons, neutrons, and electrons.
What is the purpose of the periodic table?
To organize elements based on their properties and atomic structure.
What is a physical property of an element?
A characteristic that can be observed without changing the substance, such as color or boiling point.
Who is credited with developing the modern atomic theory?
John Dalton.
Where are protons and neutrons located in an atom?
In the nucleus.
What are groups in the periodic table?
Vertical columns that group elements with similar properties.
Give an example of a chemical property.
Reactivity with oxygen.
What distinguishes one element from another at the atomic level?
The number of protons in the nucleus.
What is the charge of an electron?
Negative.
What do the rows in the periodic table represent?
Periods, indicating the energy levels of electrons.
What is the difference between metals and nonmetals in terms of properties?
Metals are usually shiny, conductive, and malleable, while nonmetals are dull, insulators, and brittle.
What does the atomic number represent?
The number of protons in an atom.
How do neutrons contribute to an atom's mass?
They add to the overall mass but do not have a charge.
What is the significance of the element's position in the periodic table?
It indicates its properties and reactivity.
What is an isotope?
Atoms of the same element with different numbers of neutrons.
How does the atomic theory explain chemical reactions?
Atoms rearrange to form new substances.
What is the mass of a proton compared to an electron?
A proton is approximately 1836 times more massive than an electron.
What are noble gases, and where are they found on the periodic table?
Elements in Group 18 that are inert and found on the far right.
How do the properties of elements change across a period on the periodic table?
They change from metallic to nonmetallic characteristics from left to right.