Question

atomic theory part 2- isotopes
quick review on early atomic theory:
an ______ is the smallest particle of an element that retains its identity in a chemical reaction. the existence of atoms as indivisible units of matter had been suggested 2,400 years ago, but these early ideas lacked experimental support and did not explain chemical behavior.

discovering subatomic particles:
john ____ , his atomic model marks the beginning of atomic theory. much of his atomic theory is accepted today, but we now know that atoms are __ . they can be broken down into smaller, more fundamental particles, called ____ particles, including electrons, protons, and neutrons.

in 1897, j.j ____ discovered __ , or negatively charged subatomic particles. thomson passed electrical current through electrodes in sealed tubes of gas. the electrons became charged, resulting in a glowing beam/cathode ray. __ rays are attracted to __ charged metal plates and are repelled by a negatively charged metal plate. since opposites attract and like charges repel, thomson deduced that cathode rays are beams of negatively charged particles he named ____ .

thomson concluded from his research that the mass of the negative charge was very small compared to the magnitude of the charge. thomson’s model can be thought of as a chocolate chip cookie or chocolate chips in ice cream. the “chips” represent the electrons evenly distributed.

diagram of a green sphere with blue dots, labeled with a blank

discovering the nucleus:
in ____ model of the atom, electrons travel around the nucleus like around the sun. rutherford experimented using __ ____ and alpha particles.

diagram of a nucleus with electrons orbiting, labeled with blanks

Explanation:

To solve the fill - in - the - blanks related to Atomic Theory (Isotopes and Subatomic Particles), we use our knowledge of the history and concepts of atomic theory:

Quick review on Early Atomic Theory:

The atom is the smallest particle of an element that retains its identity in a chemical reaction.

Discovering Subatomic Particles:

John Dalton - his atomic model marks the beginning of atomic theory. Much of his atomic theory is accepted today, but we now know that atoms are divisible. They can be broken down into smaller, more fundamental particles, called subatomic particles, including electrons, protons, and neutrons.

In 1897, J.J Thomson discovered electrons, or negatively charged subatomic particles. Thomson passed electrical current through electrodes in sealed tubes of gas. The electrons became charged, resulting in a glowing beam/cathode ray. Cathode rays are attracted to positively charged metal plates and are repelled by a negatively charged metal plate. Since opposites attract and like charges repel, Thomson deduced that cathode rays are beams of negatively charged particles he named electrons.

Discovering the Nucleus:

In Rutherford's model of the atom, electrons travel around the nucleus like planets around the sun. Rutherford experimented using gold foil and alpha particles.

Answer:

s (filling the blanks in order):

1. atom
2. Dalton
3. divisible
4. subatomic
5. Thomson
6. electrons
7. Cathode
8. positively
9. electrons
10. Rutherford's
11. gold foil