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Structure of Atoms
Atom History
Atom Basics
Atom Fun Facts
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100
What does an atom look like? Draw it.
Judged Answer
100
Where are electrons found?
electrons are found in orbits around the nucleus
100
What is an atom?
the basic unit of a chemical element particles as a source of nuclear energy
100
Which two particles would be attracted to each other? A. electrons and neutrons B. electrons and protons C. protons and neutrons D. all particles are attracted to each other
B. electrons and protons
100

Who is the teacher of Democritus?

Leucippus

200

What are the subatomic particles of an atom?

protons, neutrons, and electrons.

200

What is the charge of neutrons?

Positive

200
When was the word "atom" invented?
Around 2500 years ago.
200
The nucleus of an atom consists of:____________
protons and neutrons
200

Who discovered the electron?

A.) J.J. Thomson B.) J. Chadwick C.) Eugen Goldstein

A. J.J Thompson

300
The mass of the atom is determined by ____________? A. neutrons B. neutron and proton C. electron D. electron and neutron
B. neutron and proton
300

Around what year did Democritus and Aristotle started their theory about atom?

Around 440 BCE

300
Who came up with the word atom?
A Greek man named Democritus.
300
A single proton has what electrical charge?
positive charge
300

If an atom was the size of a football stadium, how big would the nucleus be? A. a sunflower B. a bee C. a human D. an elephant

B. a bee

400
Almost the entire mass of an atom is concentrated in the _____?
nucleus
400
How did the atom obtain its name?
The word is derived from the Greek word "atomos", meaning indivisible.
400
According to atomic theory, electrons are usually found:___________
outside the nucleus and often far from it - most of an atom's volume is its electron cloud
400
Which particles have approximately the same size and mass as each other?
protons and neutrons
400

Who discovered the electron?

A.) J.J. Thomson B.) J. Chadwick C.) Eugen Goldstein

B.) J. Chadwick

500
An element is determined by the number of:
protons
500
A beryllium atom has 4 protons, 5 neutrons, and 4 electrons. What is the mass number of this atom? A. 4 B. 5 C. 9 D. 13 E. 8
C. 9
500
An atom has a mass number of 23 and atomic number 11. The number of protons are _____________. A. 11 B. 12 C. 23 D. 44
A. 11
500
What is the atomic number of helium? Don't look at the periodic table. The judge is at the back. If you look, you will lose 1000 points.
2
500

How many carbon atoms wide is the average human hair?

one million carbon atoms