WHO MADE THESE ATOMIC DISCOVERIES?
An atom has a nucleus that is very small
In a reaction, the mass of the products must equal the mass of the reactants.
Electrons are negatively charge pieces of matter.
An electron has a mass that is very small compared to the size of the atom.
The charge to mass ratio of an electron
Any sample of a chemical compound will contain the same elements in the same
proportions.
Neutrons are a particle with no charge.
The magnitude of an electron's charge
I am fairly certain all these are in your text. Have you read that?
I will be happy to critique your work. You should know each one of these.
I am very sorry. Chem is just not my thing and i looked in my notes the book and everything
Bobpursley asked if you'd READ the text. Just looking in it for the answers does not help you learn. You need to READ carefully, take notes, and study your text to understand what you need to learn.
The atomic discoveries you mention were made by various scientists throughout history. Here's a breakdown of the discoveries and the scientists associated with them:
1. An atom has a nucleus that is very small: This discovery is credited to Ernest Rutherford, a New Zealand-born physicist, in the early 20th century. Through his famous gold foil experiment, Rutherford concluded that atoms have a small, dense and positively charged nucleus at their center.
2. Law of Conservation of Mass: The discovery that in a reaction, the mass of the products must equal the mass of the reactants is attributed to Antoine Lavoisier, a French chemist, in the late 18th century. Lavoisier's experiments and observations led to the formulation of this fundamental principle.
3. Electrons are negatively charged particles of matter: This discovery is associated with J.J. Thomson, an English physicist, who in the late 19th century conducted experiments to investigate electric currents passing through gas discharge tubes. Through his work, Thomson discovered that these tubes emitted negatively charged particles, which he named electrons.
4. An electron has a significantly smaller mass compared to the size of the atom: This realization was a result of the combined efforts of various scientists, such as J.J. Thomson and Robert A. Millikan. Thomson's experiments with cathode rays determined the charge-to-mass ratio of electrons, while Millikan's oil drop experiment accurately measured the charge of an electron. By combining these findings, scientists deduced that electrons have a mass much smaller than that of the atom as a whole.
5. Neutrons are particles with no charge: James Chadwick, an English physicist, is credited with the discovery of neutrons in 1932. Through a series of experiments, Chadwick observed that certain types of atoms emitted particles with no charge during a nuclear reaction. He named these particles "neutrons," as they were electrically neutral.
6. The magnitude of an electron's charge: The exact magnitude of an electron's charge was determined by Robert A. Millikan in 1909 using his oil drop experiment. He found that the magnitude of an electron's charge is approximately 1.6 x 10^-19 coulombs.
These discoveries, made by various scientists over time, have contributed significantly to our understanding of atomic structure and the nature of matter.