1.Type of bonding in which electrons are completely transferred is called ionic bond.
2. Isotopes have same atomic number but different atomic mass number.
Atomic number = number of protons + number of neutrons
Therefore, A is correct.
3. Nucleus is composed of neutrons and protons.
4. Chemical reactions follows the law of conservation of mass. Therefore mass of reactant = mass of product = 4 grams.
5. Again, mass of table salt formed should be equal to mass of (Na+Cl₂) = 4 grams.
The labeled diagram is given in the image attached.
As it can be seen from the image that freezing is when energy is removed from the system at 0 ⁰ while melting is when energy is added at 0⁰.
Also when energy is added at 100⁰C, it causes boiling while when it is removed at 100⁰C, it causes condensation.
Melting point of water is 0⁰C while boiling point is 100⁰C
I believe it means idea because a Web is out line to a a more structured idea
6 miles of H2O is equal to 12 Hydrogen molecules and 6 oxygen molecules. Equaling 18 in total.