Answer:
Nucleus
Explanation:
The nucleus serves as the cells command center, sending direction to the cell to grow, mature, divide, or die
Lavoisier is known as the “Father of Modern Chemistry” or the “Father of Chemistry”.
He is famous for isolating oxygen and establishing the law of conservation of mass.
Arrangement of atoms or group of atoms in a three dimensional ordered pattern in a crystal is said to be a crystalline lattice. They are arranged in a specific pattern with high symmetry. The heating of the crystal at high temperature will result in the increase of vibrational kinetic energy of the atoms in the crystal and this will result in the breaking of lattice apart and due to the breaking of lattice apart the ions will flow freely.
Thus, the heating of a solid at high temperature will lead to the lattice breaks apart and ions will flow freely.
Answer: a) 
b) 
c) 
d) 
Explanation:
General representation of an element is given as:_Z^A\textrm{X}
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
In an atom, when neutrons or protons are lost or gains, it directly affects the mass number of an atom.
Atomic number is defined as the number of protons or number of electrons that are present in an atom.
It is characteristic of a particular element.
Atomic number = Number of electrons = Number of proton
a) Z 74, A 186: 
b) Z 80, A 201: 
c) Z 34, A 76: 
d) Z 94, A 239.: 
Explanation:
both reduction and oxidation are occurring simultaneously, this is known as a redox reaction. An oxidizing agent is substance which oxidizes something else. In the above example, the iron(III) oxide is the oxidizing agent. A reducing agent reduces something else