Answer:
Niels Bohr proposed a model of the atom in which the electron was able to occupy only certain orbits around the nucleus. This atomic model was the first to use quantum theory, in that the electrons were limited to specific orbits around the nucleus.
Ernest Rutherford is known for his pioneering studies of radioactivity and the atom. He discovered that there are two types of radiation, alpha and beta particles, coming from uranium. He found that the atom consists mostly of empty space, with its mass concentrated in a central positively charged nucleus.
On April 30, 1897, British physicist J.J. Thomson announced his discovery that atoms were made up of smaller components. This finding revolutionized the way scientists thought about the atom and had major ramifications for the field of physics.
What is Dalton's atomic theory?
A theory of chemical combination, first stated by John Dalton in 1803. It involves the following postulates: (1) Elements consist of indivisible small particles (atoms). (2) All atoms of the same element are identical; different elements have different types of atom. (3) Atoms can neither be created nor destroyed.
The theory of Democritus held that everything is composed of "atoms," which are physically, but not geometrically, indivisible; that between atoms, there lies empty space; that atoms are indestructible, and have always been and always will be in motion; that there is an infinite number of atoms and of kinds of atoms,
Explanation:
Answer: It showed that all atoms contain electrons.
Explanation:
- J.J. Thomson's experiments inside a cathode ray tube in the presence of an electric field showed that all atoms contain tiny negatively charged subatomic particles "electrons".
- Also, Thomson's plum pudding model of the atom had negatively-charged electrons embedded within a positively-charged "soup."
- Furthermore, Rutherford's gold foil experiment showed that the atom is mostly empty space with a tiny positively-charged nucleus.
- Then, Rutherford proposed the nuclear model of the atom based on these results.
The equation is already balanced.
Answer:
In a chemical reaction, there is a change in the composition of the substances; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition.
Explanation:
Explanation:
When we have direct sunlight, the temperature is higher compared to indirect sunlight.
Direct sunlight is usually overhead whereas indirect sunlight is at an angle to the surface.
- Direct sunlight impacts the surface with more energy concentrated on a smaller surface area.
- This warms the surface more.
- Indirect sunlight is diffuse and spreads over a wider area.
- This leads to a reduction in temperature.
