Answer:
Explanation:B ice melting is a phiyscal change and the mass of the substance remains the same
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.
Answer: Friction is a force that resists relative motion between two surfaces in contact. Depending on the application, friction may be desirable or undesirable.
