To develop the chemical formula of a substance or compound in this regard, one only needs to write the chemical symbol for each of the element present and write as subscript to each symbol the number of atoms of that element. For nitrobenzene, as described above, the chemical formula should be,
C₆H₅O₂N
Answer:
The building block that makes up all matter in the universe is atoms.
Answer:We will use an acid to test whether sample contains calcium carbonate or not.
Explanation:
Calcium carbonate reacts with acids to give off carbon-dioxide gas ,water and calcium chloride. it is a salt of strong base calcium hydroxide and weak acid carbonic acid.
Evolution of carbon-dioxide on the reaction is also termed as effervescence.
If the sample contains the calcium carbonate strong effervesces will be observed and if not no effervescence will be observed.
We will use an acid to test whether sample contains calcium carbonate or not.
Answer:
Atom is the building block of matter. The atom itself made up of subatomic particles electron, proton and neutron.
Explanation:
Long time ago, Greek philosopher thoughts that matter can be divided into smaller particles until a point is reached when the basic unit is obtained which can not be further sub divided. A Greek philosopher Democritus called these basic units "Atom".
Later on modern research showed that atom could be divided into smaller particles electron, proton and neutron. These smaller particles are called sub-atomic particles of atom.
Atoms are the fundamental unit of matter. Every thing in the universe that occupy space and have mass is called matter. we can say that every matter is composed of atoms. while the atom is composed of subatomic particles called electron proton and neutron.
Electron:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Symbol = e-
Mass= 9.10938356×10-31 Kg
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
Proton and Neutron:
An atom consist of positively charged central core (nucleus) that is made up of Proton and neutron. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P+
Symbol of neutron= n0
Mass of proton=1.672623×10-27 Kg
Mass of neutron=1.674929×10-27 Kg
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons.
