Network solids are hard and have high melting points. which statement explains these properties?
a.
the atoms are held together with large networks of metallic bonds.
b.
the atoms are held together with large networks of electromagnetic forces.
c.
the atoms are held together with large networks of intermolecular forces.
d.
the atoms are held together with large networks of covalent bonds.

The correct answer is A the atoms are held together with large network of metallic bonds.

Explanation:

Metallic bond is a specific type of bond that is formed by interaction of many detached negatively charged electron with positively charged ions or cations,which provides a definite structure to the substance.

Due to the low ionization energy the electrons present in the outerorbital can be de localized throughout the metal.The de localized electrons able to freely move around the crystalline structure.

 There is a presence of strong interaction between negatively charged electrons and positively charged ions which is responsible for high melting and boiling point of metals.

it is to be noted that an alpha particle is an helium nucleus. so it contains 2 protons 2 neutrons and has a mass number of 4. when alpha decay particles are ejected from the nucleus it gets transformed into an atom which has atomic number less than 2 and a mass number less than 4.

an equation that could represent alpha decay is radium 226 decay of alpha particle forms radon 222.

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