Rtucat page 13 Flashcards
(19 cards)
What is the smallest unit of matter?
An atom
An atom is composed of protons, neutrons, and electrons.
What charge do protons have?
Positively charged
Protons are found in the nucleus of an atom.
What is the charge of neutrons?
No charge
Neutrons are also located in the nucleus.
Where do electrons orbit?
The nucleus
Electrons are negatively charged.
Which element typically has no neutrons?
Hydrogen
Hydrogen usually consists of just one proton.
How are elements arranged in the periodic table?
In order of increasing atomic number
Atomic number refers to the number of protons.
What are the three categories of elements in the periodic table?
- Metals
- Metalloids (semimetals)
- Nonmetals
These categories reflect the properties of the elements.
What do elements in the same group of the periodic table have in common?
The same number of valence electrons
They also share similar properties.
What do elements in the same period of the periodic table share?
The same highest electron energy level
Periods are the rows of the table.
What is an ionic bond?
A bond formed between atoms with very different electronegativity values
Typically involves a metal and a nonmetal.
How are covalent bonds formed?
Atoms share electrons
Covalent bonds typically occur between nonmetal atoms.
What characterizes metallic bonds?
Metals share valence electrons, forming an electron sea
This structure allows for the formation of alloys.
What occurs during nuclear fission?
A heavy nucleus is bombarded by neutrons, decomposing into two nuclei
This process releases energy.
What is nuclear fusion?
Light atoms are smashed together, releasing energy
This process powers the sun and other stars.
What does the Mohs hardness scale measure?
The relative hardness of minerals
The scale ranges from 1 (talc) to 10 (diamond).
What does Hubble’s Law state?
The universe is expanding, and galaxies are moving away from each other
The rate is proportional to their distance.
What is the Big Bang Theory?
The universe began from a hot, dense state and has been expanding ever since
This theory explains the origin of the universe.
What are Sir Isaac Newton’s three laws of motion?
Fundamental laws important for understanding motion of objects and forces
These laws are significant in many areas of chemistry.
What are electromagnetic waves?
A type of wave that travels through space, including light, radio waves, and X-rays
Important in spectroscopy, a technique used to identify and study molecules.
