When a cloud of gas and dust in space was disturbed, maybe by the explosion of a nearby star.This explosion made waves in space which squeezed the cloud of gas & dust.
Australia separated from other continents and species there evolved independently
Answer:
Explanation:
The original equation is:
We notice that:
- we have 1 atom of Fe on the left, and 2 atoms of Fe on the right
- we have 2 atoms of O on the left, and 3 atoms of O on the right
Therefore, the equation is not balanced.
In order to balance it, we can add:
- a coefficient 3 in front of 
- a coefficient 2 in front of 
So we have:
Now the oxygen is balanced, but the iron it not balanced yet, since we have 1 Fe on the left and 4 on the right. Therefore, we should add a coefficient 4 on the Fe on the left:
Answer: An iron atom emits particles when it is struck by light (by the photoelectric effect)
Explanation:
The first atomic model was the one proposed by Jhon Dalton, according to which it is postulated that:
"Matter is made up of indivisible, indestructible and extremely small particles called atoms."
That is, <u>the atom is a solid and indivisible mass.
</u>
However, the fenomenom by which an iron atom emits particles when it is struck by light (known as the photoelectric effect) can not be explaind by this<u> indivisible atom</u> model.
To understand it better:
The <u>photoelectric effect</u> consists of the emission of electrons (electric current) that occurs when light falls on a metal surface under certain conditions.
This is possible by considering light as a stream of photons, where each of them has energy. <u>This energy is be able to pull an electron out of the crystalline lattice of the metal and communicate, in addition, a kinetic energy. </u>This means the atom is not indivisible, but it is a composition of different particles.
In fact, currently it is known that each atom is composed of a nucleus and one or more electrons attached to the nucleus, which is composed of one or more protons and typically a similar number of neutrons.
