(25-26) Unit 2: Atomic Structure

Class competion!

At the end of each unit, the class with the least # of missing assignments will get a prize!

*Which 2 parts of Dalton's theory were

incorrect?

​1.) ELEMENTS ARE MADE OF TINY INDIVISIBLE PARTICLES CALLED "ATOMS." 

2.) ALL ATOMS OF A GIVEN ELEMENT ARE IDENTICAL AND HAVE THE SAME MASS; ATOMS OF DIFFERENT ELEMENTS ARE DIFFERENT. 

3.) ATOMS OF DIFFERENT ELEMENTS COMBINE TO FORM CHEMICAL COMPOUNDS. IN ANY COMPOUND, THE ATOMS OF DIFFERENT ELEMENTS ARE COMBINED IN A DEFINITE WHOLE NUMBER RATIO. 

4.) ATOMS CAN NEITHER BE CREATED NOR DESTROYED BY A CHEMICAL REACTION, MERELY GROUPED TOGETHER IN DIFFERENT WAYS.

Multiple Select

Which 2 parts of Dalton's theory were INCORRECT?

• ELEMENTS ARE MADE OF TINY INDIVISIBLE PARTICLES CALLED "ATOMS." 

• ALL ATOMS OF A GIVEN ELEMENT ARE IDENTICAL AND HAVE THE SAME MASS

• ATOMS OF DIFFERENT ELEMENTS COMBINE TO FORM CHEMICAL COMPOUNDS. IN ANY COMPOUND, THE ATOMS OF DIFFERENT ELEMENTS ARE COMBINED IN A DEFINITE WHOLE NUMBER RATIO. 

• ATOMS CAN NEITHER BE CREATED NOR DESTROYED BY A CHEMICAL REACTION, MERELY GROUPED TOGETHER IN DIFFERENT WAYS.

• ATOMS OF DIFFERENT ELEMENTS ARE DIFFERENT. 

Multiple Choice

Which scientist believed that matter was made up of small indivisible particles called 'atomos'?

• Plato

• Aristotle

• Democritus

• John Dalton

Multiple Choice

This was the first model of the atom ever proposed. It was simple and described atoms as tiny spheres that could not be broken down into smaller pieces.

• Democritus's model of the atom

• The "Plum Pudding Model" of the atom

• The "Rutherford Model" of the atom

• The "Quantum Mechanical Model" of the atom

Multiple Choice

According to the Plum Pudding Model, what did Thompson propose about the structure of the atom?

• The atom is a uniform positive 'pudding' with negative particles embedded in it.

• The atom has a dense nucleus with electrons orbiting around it.

• The atom is mostly empty space with a small dense core.

• The atom is made up of indivisible particles.

Multiple Choice

What did Rutherford conclude?

• Atoms are mostly empty space; atoms contain a small dense region of positive charge called the nucleus; the mass of the atom is concentrated in the nucleus

• Atoms are mostly solid; atoms contain electrons in fixed orbits; the mass of the atom is spread evenly

• Atoms are made only of electrons; atoms have no nucleus; the mass of the atom is negligible

• Atoms are indivisible; atoms cannot combine; the mass of the atom is not important

Multiple Choice

This model was developed after J.J. Thompson discovered electrons, a particle smaller than an atom. Is shows electrons floating freely in a positive space.

• The "Plum Pudding Model" of the atom

• The "Rutherford Model" of the atom

• Democritus's model of the atom

• The "Quantum Mechanical Model" of the atom

Multiple Choice

Ernest Rutherford discovered that atoms were mostly _________________. 

• negatively charged
• positively charged
• electrons
• empty space. 

Multiple Select

This is the most complete and current model of the atom. Electrons are located in complex orbitals. (Check all that apply)

• The "Quantum Mechanical Model" of the atom
• The "Rutherford Model" of the atom
• The "Plum Pudding Model" of the atom
• The "wave mechanical model" of the atom

• The "Electron cloud model" of the atom

Multiple Choice

What can you conclude from the fact that scientists continue to update the atomic model?

• New information about atoms continues to be discovered

• Old information about atoms is completely useless

• Scientists did not have any information about atoms until a few years ago

• Scientists still have no idea what atoms look like

Multiple Choice

Which of the following is NOT a topic covered in Unit 2: Atomic Structure?

• Hybrid Orbitals

• Lewis Dot Structures

• Chemical Bonding

• Isotopes

Open Ended

What is one topic you are most interested in learning more about from Unit 2: Atomic Structure?