Advertisement Upgrade to remove ads

This is on the structure of the Atom


T or F? Ancient philosophers regularly performed controlled experiments


T or F? Philosophers formulated explanations about the nature of matter based on their own experiences


T or F? Both Demcritus and Dalton suggested that matter is made up of atoms


T or F? Dalton's atomic theory stated that atoms separate, combine, or rearrange in chemical reactions


T or F? Dalton's atomic theory stated that matter is mostly empty space


T or F? Dalton was correct in thinking that atoms could not be divided into smaller particles


T or F? Dalton's atomic theory stated that atoms of different elements combine in simple whole-number ratios to form coumpounds.


T or F? Dalton thought that all atoms of a specific element have the same mass.


T or F? Democritus proposed that atoms are held together by chemical bonds, but no one believed him.


T or F? Dalton's atomic theory was based on careful measurements and extensive research.


Who proposed the nuclear atomic model?


Who determined the mass-to-charge ratio of an electron?


Who calculated the mass of an electron?

Plum pudding model

In this model, the atom is composed of electrons (which Thomson still called "corpuscles," though G.J. Stoney had proposed that atoms of electricity be called electrons in 1894), surrounded by a soup of positive charge to balance the electron's negative charge, like plums surrounded by pudding.

Nuclear atomic model

A theory of atomic structure in which nearly all the mass is concentrated in a small nucleus, electrons surrounding the nucleus fill nearly all the atom's volume, the number of these electrons equals the atomic number, and the positive charge on the nucleus is equal in magnitude to the negative charge of the electrons

Proton (P) location


Neutron (N) location


Electron (e-) location

space around the nucleus


What is the relative charge of a Proton?


What is the relative mass of a Proton?


What is the relative charge of a Neutron?


What is the relative mass of a Neuton?


What is the relative charge of an Electron?


What is the relative mass of an Electron?


T or F? The number of neutrons in an atom is referred to as its atomic number


T or F? The periodic table is arranged by increasing atomic number.


T or F? Atomic number is equal to the number of electrons in an atom.


T or F? The number of protons in an atom identifies it as an atom of a particular element.


T or F? Most atoms have either a positive or a negative charge.

82 protons, 82 electrons

Lead has an atomic # of 82. How many protons and electrons does lead have?


Oxygen has 8 electrons. How many protons does oxygen have?


Zinc has 30 protons. What is its atomic number?


Astatine has 85 protons. What is its atomic number?

104 protons, 104 electrons

Rutherfordium has an atomic # of 104. How many protons and electrons does it have?

84 protons, 84 electrons

Polonium has an atomic # of 84. How many protons and electrons does it have?

102 protons, 102 electrons

Nobelium has an atoic # of 102. How many protons and electrons does it have?

19 protons, 19 electrons, 20 neutrons

# of P, E, & N's- An isotope has atomic # 19 and mass number 39.

14 protons, 14 neutrons

# of P, E, & N's- An isotope has 14 electrons and a mass # of 28

19 protons, 19 electrons

# of P, E, & N's- An isotope has 21 neutrons and a mass # of 40

51 protons, 51 electrons, 72 neutrons

# of P, E, & N's- An isotope has an atomic # 51 and a mass # 123

smaller than the mass of a proton and a neutron, and a tiny fraction of the mass of an atom

The mass of an electron is....

1/12 the mass of a carbon-12 atom

One atomic mass unit is

both the relative abundance and the mass of each of the atom's isotopes

The atomic mass of an atom is usually not a whole # because it accounts for


Everything we know at the atomic level has been measured ___________

460-370 BC

time period of Democritus


time period of John Dalton


time period of J.J. Thomson


time period of Ernest Rutherford


time period of Niels bohr


Who 1st proposed that matter was made up of tiny particles called atoms?


Who stated atoms could not be created, destroyed, or further divided?


Who proposed the Atomic Theory in 1803?


Who took half a century until he was well accepted?


It took 100 years until __________ was prove

J.J. Thomson

Who discovered electrons in 1897?


Chemistry is driven by ___________

J.J Thomson

Who made the Plum Pudding Model?


Pudding's Charge


Plum's Charge


Gold foil experiment 1909-mass concentrated in very small core at the atom's center (nucleus)


Doctoral Thesis 1911- Theory of Electrons

James Chadwick

Who identified the neutron?

Nucleus, and the Electron Cloud

What are the 2 main parts of an atom?

protons (+) and neutrons (0)

Nucleus contains:


Mass of an atom is measured in _________


Protons and neutrons are found in the nucleaus, so it has a ______ charge


Electrons are found in the electron cloud, so it has a _____________ charge


1 _______ is defined as 1/12 teh mass of a carbon atom containing 6 protons and 6 neutrons


1________ is also the mass of 1 proton or 1 neutron


An electron has a mass of __________ amu

Atomic Number

the number of protons in the nucleus of an atom

Mass Number

the sum of the # of protons and the # of neutrons in the nucleus


#protons + # neutrons


atoms of the same element with differing #'s of neutrons


isotopes have different ____________

average atomic mass

the average mass of the mixtures of its isotopes


Isotopes containing more neutrons have a greater __________

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording