Structure of atom

the central region of an atom where its neutrons and protons are is its 

• nucleus 
• electron cloud
• core 
• center 

Tags

NGSS.MS-PS1-1

What is the mass of an atom if it has 11 protons, 12 neutrons, and 11 electrons?

• 22
• 11
• 34
• 23

Tags

NGSS.MS-PS1-1

Who discovered the electron?

• Rutherford

• Thomson

• Milikan

• Dalton

Who first proposed that everything in the world was made up of tiny particles?

• Aristotle
• Democritus
• Plato
• Socrates

Which philosopher stated that matter was made of four elements: earth, wind, water and fire?

• Aristotle
• Democritus
• Plato
• Socrates

Dalton showed that common substances always broke down into _____

• the same elements in the same proportions
• elements in equal quantities
• hydrogen and oxygen
• earth, wind, water and fire

Tags

NGSS.HS-PS1-7

The electron was discovered in 1897.  Who discovered it?

• Ernest Rutherford
• John Dalton
• J. J. Thomson
• Niels Bohr

Who concluded that atoms consisted largely of empty space with most of the mass concentrated in the center?

• J. J. Thomson
• Max Planck
• Ernest Rutherford
• Niels Bohr

This picture best represents ___________________ atomic model.

• Thomson's

• Dalton's

• Bohr's

• Chadwick's

Which of the following is/are conclusions based on Rutherford’s gold foil experiment?

• Atom is mostly empty space

• The nucleus is positively charged

• The atom has a small dense nucleus

• All answers are correct