structure of the atom

Thompson was the first to discover a subatomic particle - the electron. What are the others?

• neutrons & positrons

• protons & neutrons

• positrons & quarks

• protons & positrons

Tags

NGSS.MS-PS1-1

A positively charged particle found in the nucleus is called a

• neutron.

• proton.

• electron.

• positron.

Tags

NGSS.HS-PS1-8

Only protons & neutrons can be distinguished by mass, charge and position in an atom.

• True

• False

Tags

NGSS.HS-PS1-8

99.9% of the atom's mass is found where?

• nucleus

• protons

• electron cloud

• neutrons

Tags

NGSS.HS-PS1-8

Electrons are

• negative

• positive

• neutral

Tags

NGSS.HS-PS2-4

The nucleus is ____________ charged.

• positively

• negatively

• neutral

Tags

NGSS.MS-PS1-1

Who discovered the electron?

• Rutherford

• Chadwick

• Thomson

• Goldstein

Why was the Thomson’s Model of an atom failed?

i. It could not explain the screening of negative charges from that of positive

ii. It did not tell about the presence of electrons

iii. It did not give an idea about the discrete energy levels

iv. It explained the atom as a whole to be electrically neutral

Choose the correct option from the following:

• Only (iii)

• Both (i) & (iii)

• Only (i)

• Both (ii) & (iv)

Which of the following statements is incorrect about the structure of an atom?

i. The whole mass of an atom is concentrated in the nucleus

ii. The atom is an indivisible particle

iii. The atom as a whole is neutral

iv. All the atoms are stable in their basic state

Choose the right option among the following:

• (i) and (iii)

• only (ii)

• (ii) and (iv)

• none of these

Which of the following correctly represent the electronic distribution in the Mg atom?

• 3, 8, 1

• 2, 8, 2

• 1, 8, 3

• 8, 2, 2

Tags

NGSS.HS-PS1-1