Answer:
Explanation:
1. Atomic numbers:
Atomic number is the number of protons in an atom. It is one of the most diagonistic and representative number used in identifying an atom. The periodic table of element arranges elements based on this number.
No two elements have the same atomic number.
Protons are positively charged particles in an atom.
- In a neutral atom, the atomic number is the same as the number electrons since electrical neutrality is attained when the number of protons and electrons are the same.
- The atomic number determines the position of an atom on the periodic table and it is unique for every atom.
2.
Periodic patterns
These are trends on that can be predicted on the periodic table because they shew regularities down a group or sometimes across the period.
Some of these trends are atomic radius, electronegativity, metallicity, nuclear charge e.t.c
Properties of elements can be predicted using these patterns even before they are discovered.
b.
Physical property shared by Helium, Argon and Neon is that they are all gases. All group 8 elements are called noble or inert gases.
Chemical property of these elements: they are chemically unreactive.
These gases are very stable having complete electronic shell configuration. Every atom on the periodic table tries to attain the state of the noble gases.
C.
Noble Gases/ Inert Gases/ Group O elements
Coffee keeps you awake due to the caffeine in it. Caffeine is considered a psychoactive drug which energizes people by releasing a chemical in the body.
Answer:-
Oxygen gains electrons and is reduced.
Explanation:-
For this reaction the balanced chemical equation is
4Fe + 3O2 --> 2Fe2O3
When Oxygen is present as oxygen gas, the oxidation number of O is Zero since it is the only element present in Oxygen gas.
Similarly Iron is present in Fe with oxidation number Zero.
In the case of Fe2O3, Oxygen has the oxidation number -2 while Iron has +3.
So the oxidation number of Oxygen goes from Zero to -2.
Since the oxidation number decreases Oxygen is reduced.
Since reduction involves gain of electrons, Oxygen gains electrons.
<span>after the 1940, the infention of : PASTEURIZATION permitted wines to be produced in places where climate was not ideal for wine production
after pasteurization process, all the microbes that exist within the wine are eliminated, which will prevent it from rottening. This make it possible to store wine for a long period of time even thought it's not in the harvesting climate</span>
