Which substance contains metallic bonds (1)hg (2)h2o (3) nacl (4)c6h12o6

(1)

Explanation:

A covalent bond is formed when an element shares its valence electron with another element. This bond is formed between two non metals. Example: and

An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and the element which accepts the electrons is known as electronegative element. This bond is formed between a metal and an non-metal. Example:

Metallic bond is defined as the bond which is formed between positively charged atoms having free electrons and are shared among a lattice of cations. This is usually formed between metals. Example:

the correct answer is:

a. formation of precipitation

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.