$$\$$ \text{Mass of electron} = \frac{1.60 \times $$10^{-19}$$ \text{ C}}{1.76 \times $$10^{8}$$ \text{ C/g}} \$$ $$

Question 1

Which statement best describes John Dalton's atomic theory as depicted in Dalton's Model?

Accepted Answer

Atoms are tiny, hard spheres that cannot be split up.

Question 2

Which property of electrical charge is illustrated when a balloon rubbed on hair sticks to a wall?

Accepted Answer

Opposite charges attract

Question 3

In the context of direct current, which direction do electrons actually flow?

Accepted Answer

From negative to positive

Question 4

Which experiment led to the discovery of the electron?

Accepted Answer

Cathode ray tube experiment

Question 5

What did J.J. Thomson conclude about cathode rays?

Accepted Answer

They are streams of negatively charged particles found in all substances.

Question 6

Which equation correctly represents the calculation of the mass of an electron using Millikan's and Thomson's results?

Accepted Answer

$$\$$ 	ext{Mass of electron} = \frac{1.60 	imes $$10^{-19}$$ 	ext{ C}}{1.76 	imes $$10^{8}$$ 	ext{ C/g}} \$$ $$

Question 7

Which type of radiation is not deflected by a magnetic field?

Accepted Answer

Gamma

Question 8

What was the main conclusion from Rutherford's gold foil experiment?

Accepted Answer

Atoms are mostly empty space with a small, dense, positively charged nucleus.

Question 9

Which subatomic particle was discovered by James Chadwick?

Accepted Answer

Neutron

Question 10

How many neutrons are in an isotope of argon with a mass number of 40 and atomic number 18?

Accepted Answer

22

Question 11

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 12

Which electronic transition in a hydrogen atom would result in the emission of visible light?

Accepted Answer

$$\ n = 5$$ \rightarrow n = 2 \$$ $$

Question 13

What is the maximum number of electrons that can occupy the fourth energy level (n = 4) of an atom?

Accepted Answer

32

Question 14

Which element has the ground state electron configuration $$\$$ $$1s^2$$ $$2s^2$$ $$2p^6$$ $$3s^2$$ $$3p^5$$ \$$ $$?

Accepted Answer

Chlorine

Question 15

How many valence electrons does a chlorine atom have?

Accepted Answer

7

Question 16

Which group of elements is known as the alkali metals?

Accepted Answer

Group 1A

Question 17

What is the electron configuration for the oxide ion ($$\$$ $$O^{2-}$$ \$$ $$)?

Accepted Answer

$$\$$ $$1s^2$$ $$2s^2$$ $$2p^6$$ \$$ $$

Question 18

Which of the following best describes the difference between metals and nonmetals?

Accepted Answer

Metals conduct electricity and are malleable, nonmetals are brittle and nonconductors.

Question 19

Which scientist is credited with the discovery of the neutron?

Accepted Answer

James Chadwick

Question 20

Which of the following statements about main-group elements in the same group of the periodic table is correct?

Accepted Answer

They have similar chemical properties.

Atomic Structure: Historical Models and Experimental Discoveries

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