Chemistry 121 Chapter 2 Part 1

Explanation
The Greeks gave the first serious thought to the question "what is matter made of?" They were the first to propose the idea that matter is composed of fundamental particles called atoms. This concept was developed by Greek philosophers such as Democritus and Leucippus around the 5th century BC. They believed that atoms were indivisible and indestructible building blocks of matter. Although their ideas were not scientifically proven at the time, they laid the foundation for modern atomic theory and our understanding of the composition of matter.

Explanation
John Dalton is the correct answer because he was the one who believed that elements were made of identical particles called atoms. This belief became the foundation of modern atomic theory. Dalton's atomic theory also proposed that atoms combine in simple ratios to form compounds and that chemical reactions involve the rearrangement of atoms. His work laid the groundwork for further advancements in the understanding of the structure and behavior of atoms.

Explanation
John Dalton believed that atoms of a given element are different from those of any other element. This is known as Dalton's atomic theory, which he proposed in the early 19th century. According to Dalton, elements are composed of indivisible particles called atoms, and each element has its own unique type of atom. He also believed that atoms combine in simple, whole number ratios to form compounds. Dalton's theory laid the foundation for modern atomic theory and greatly contributed to our understanding of the nature of matter.

Explanation
John Dalton is the correct answer because he proposed the atomic theory, which states that atoms of different elements can combine to form compounds. He also suggested that compounds always have the same relative numbers of types of atoms. This theory revolutionized our understanding of chemistry and laid the foundation for modern atomic theory.

Explanation
John Dalton is the correct answer because he is known for his atomic theory, which states that atoms cannot be created, divided into smaller particles, or destroyed in any chemical process. This theory was a significant contribution to the understanding of atoms and laid the foundation for modern chemistry. The Greeks and J.J. Thompson also made important contributions to the field of atomic theory, but Dalton's theory specifically addresses the immutability of atoms.

Explanation
During the 19th century, scientists made significant advancements in understanding the structure of atoms. They conducted various experiments and developed theories such as Dalton's atomic theory, which proposed that atoms were indivisible and had specific properties. Additionally, discoveries such as the electron by J.J. Thomson and the nucleus by Ernest Rutherford further contributed to the understanding of atomic structure. Therefore, the 19th century was a crucial period in the scientific pursuit of determining the true nature of atoms.

Explanation
An atom is the basic unit of any element that can enter into interaction with other elements in a chemical reaction. Atoms are composed of protons, neutrons, and electrons. Protons have a positive charge, electrons have a negative charge, and neutrons have no charge. In a chemical reaction, atoms can bond together to form molecules by sharing or transferring electrons. Therefore, atoms are the fundamental building blocks of matter and play a crucial role in chemical reactions.

Explanation
The given correct answer is "Atomic Theory". This is because the basic unit of any element that can interact with other elements in a chemical reaction is an atom. The concept of atoms forming the fundamental building blocks of matter and being able to combine and interact with each other is the basis of the Atomic Theory. Dalton's Law and Thompson's Theory are not relevant to the definition of the basic unit of an element in a chemical reaction.

Explanation
J.J. Thompson discovered the electron.

Explanation
J.J. Thompson discovered the electron in 1906. This groundbreaking discovery was made during his experiments with cathode rays. Thompson's experiments provided evidence for the existence of negatively charged particles, which he named electrons. His discovery revolutionized our understanding of atomic structure and laid the foundation for further advancements in particle physics.

Explanation
Thompson found that the cathode rays did bend under the influence of an electric field. This suggests that the cathode rays are charged particles, as charged particles are known to be deflected by electric fields.

Explanation
Thompson concluded that the cathode rays were made of particles which he called "corpuscles". This term was used to describe the small, negatively charged particles that we now know as electrons. Thompson's discovery of the corpuscles provided evidence for the existence of subatomic particles and laid the foundation for our understanding of atomic structure.

Explanation
The term "sub-atomic particles" is used to describe particles that are smaller than atoms, such as protons and neutrons. In this context, the corpuscles mentioned in the question are said to come from within the atoms of the electrodes themselves, indicating that they are sub-atomic particles.

Explanation
Sub-atomic particles refer to particles that are smaller than atoms. Electrons are sub-atomic particles with a negative charge that orbit around the nucleus of an atom. Neutrons and protons are also sub-atomic particles, but they are found within the nucleus of an atom. Therefore, electrons are another name for sub-atomic particles.

Explanation
Electrons orbit around the nucleus of an atom. Protons and neutrons are located within the nucleus, while electrons move in specific energy levels or orbitals outside the nucleus. These negatively charged particles are responsible for the chemical properties of an element and participate in chemical reactions by transferring or sharing electrons with other atoms. The arrangement of electrons in different energy levels determines the stability and reactivity of an atom.