48 terms

Chapter 12 Science


Terms in this set (...)

All atoms of one element have the same number of ____________.
Why are some atoms of the same element heavier than others?
Different numbers of neutrons in their nuclei
What are atoms that have the same number of protons but different numbers of neutrons called?
How many isotopes does hydrogen have?
What is the maximum number of neutrons a hydrogen isotope can have?
What is the sum of the number of neutrons and the number of protons in a nucleus called?
Atomic mass
What are the 3 isotopes for carbon?
carbon-12, carbon-13, carbon-14
What was the name of the great philosopher who first used the term "atom" 2400 years ago?
What was the name of the English scientist that published his atomic theory of matter in 1808?
John Dalton
Who identified the "raisins in a plum pudding" model of atoms?
J. J. Thomson
Who tested the plum pudding model?
Ernest Rutherford
When tested, was the plum-pudding model proven correct or incorrect?
What did Ernest Rutherford hypothesize that atoms mostly were?
Empty Space
Who suggested that electrons orbit at different distances from the nucleus?
Neils Bohr
Today, electrons are usually shown as what around the nucleus?
a cloud
What is the smallest unit of an element that can still be identified as that element called?
An Atom
What type of subatomic particle has a positive electric charge?
What type of subatomic particle has no charge?
What type of subatomic particle has a negative charge?
How many neutrons does a nucleus usually contain?
One or more
Which type of subatomic particle is the smallest out of the three?
Which types of subatomic particles are found in the nucleus of an atom?
protons and neutrons
Where in atoms can you find electrons?
Orbiting the nucleus
Does an atom have the same number of protons and electrons or electrons and neutrons?
Protons and electrons
What are the elements in the periodic table arranged by?
atomic number
What is the temperature at which a liquid becomes a gas called?
boiling point
What is a substance made of two or more elements called?
What an element that is shiny and bends and conducts heat and electricity called?
What is the temperature at which a solid becomes a liquid called?
melting point
What is a pure substance that contains only one kind of atom called?
What is the dense center of an atom called?
What is a subatomic particle with a negative charge called?
What is hot gas containing charged and uncharged atom and free electrons called?
What is the smallest unit of pure substance that still has the identity of that substance called?
What is the model of the atom as we understand it today?
A model that has changed many times as experiments yielded new information.
How are protons and neutrons like?
Both are found in the nucleus of an atom
What is the major cause of changes in states of matter?
The change of speed of atoms or molecules.
True or False:
The number of neutrons determines the isotope.
What is a substance that is composed of 2 atoms of hydrogen, 1 atom of sulfur, and 4 atoms of oxygen?
A compound
How is the element with atomic number 82 in the periodic table different from the element that is 81 on the periodic table?
It has one more proton.
What can you infer about two substances that have the same atomic number but different atomic masses?
They are different isotopes. This means that they have the same number of protons and different number of neutrons.
What can you infer about elements that are in the same column of the periodic table?
I can infer that that they have similar properties.
The water in a pot is brought to a boil. A student measures the temperature of the water in the pot every 5 minutes for 20 minutes as the water boils. How much does the temperature change during the 20 minutes?
The water will not go over 100 degrees Celsius. It is the boiling point of water.
What is the element whose atomic symbol is C and the atomic number is 6?
How many protons does Carbon have?
How many electrons does Carbon have?
How many protons does hydrogen have?
How many protons does oxygen have?