Electrons Flashcards
Nothing was known about atoms before electrons were discovered.
False
What evidence from the cathode ray tube experiment support the claim that electrons have a negative charge?
The cathode ray bent away from a negatively charged plate.
The cathode ray bent toward a positively charged plate.
Which statement(s) about electrons is/are TRUE?
a
When they were first discovered, they were named “corpuscles.”
b
They have a unique charge-to-mass ratio depending on the element.
c
They have a tiny but significant mass.
d
They have a negative charge.
a
When they were first discovered, they were named “corpuscles.”
c
They have a tiny but significant mass.
d
They have a negative charge.
Which of the following scientists discovered the electron?
J.J Thomson
____
are negatively charged, and are one of the types of particle which make up atoms.
Electrons
Which of the following best describes how Thomson concluded that electrons are present in all atoms.
The charge-to-mass ratio of electrons is always the same constant, no matter which substances are used in the cathode ray tube.
Before J.J. Thomson began gathering evidence about electrons in 1897, what did scientists know about atoms?
Scientists generally thought atoms were the smallest particles that could not be broken down any further.
How many valence electrons does beryllium have?
2
What source supplied the electrons in J.J. Thomson’s cathode ray tube experiment?
a simple electric current allowed electrons to flow through the tube
Electrons can be deflected by a magnetic field.
true
