Which of Dalton's statements was proven false by J.J. Thomson?

• atoms cannot be subdivided

• atoms are tiny

• atoms of different elements are not identical

• atoms join to form molecules

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NGSS.MS-PS1-1

If an atom has a mass of 35.45 and contains seventeen electrons, its atomic number must be?

• 35.45

• 17

• 18

• no idea

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NGSS.MS-PS1-1

According to the modern model of atoms?

• moving electrons form electron clouds

• electrons and neutrons orbit the nucleus

• neutrons have a positive charge.

• the number of protons varies for the same element

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NGSS.MS-PS1-1

Magnesium (Mg) has twelve protons; how many valence electrons does it have?

• 2

• 8

• 12

• 24

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NGSS.MS-PS1-1

What subatomic particle can be found in regions called orbitals or clouds?

• protons

• neutrons

• electrons

• photons

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NGSS.MS-PS1-1

Identify the element shown in the Bohr orbital model:

• Boron

• Carbon

• Oxygen

• Fluorine

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NGSS.MS-PS1-1

Match the following

• Discovered the nucleus

• Ruhterford

• Said all atoms of same element were same

• Thomson

• Discovered electrons

• Democritus

• Coined the term atom

• Dalton

• Said atoms were mostly empty space

• Bohr

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NGSS.MS-PS1-1

NGSS.MS-PS1-5

Match the following

• Came up with electrons in clouds

• Dalton

• Said atoms were "uncuttable"

• Bohr

• Discovered protons and neutrons

• Democritus

• Plum-pudding model

• Rutherford

• Said elements could form compounds

• Thomson

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

Organize these options into the right categories

Groups:

(a) Dalton

,

(b) Democritus

• Thought atoms were uncuttable; NO EVIDENCE

• Thought atoms were undividable; had evidence

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NGSS.MS-PS1-1

Thomson came up with the ​ (a)   model of atoms, while Rutherford proposed the ​ (b)   model, later Bohr came up with the electron ​ (c)   model.

• plum pudding
• orbital
• cloud

Tags

NGSS.MS-PS1-1