Atom X has a total of 52 elementary particles and a mass number of 35. X's atomic number is

17

Explanation:

The number of elementary particles in the atom X = 52

The mass number of atom X = 35

The information required = The atomic number

The number elementary particles of the atom = The number of protons + The number of neutrons + The number of electrons

The mass number of an atom = The number of protons + The number of neutrons

∴ The number of electrons = The number elementary particles of the atom - The number elementary particles of the atom

The number of electrons = 52 - 35 = 17

In a neutral atom, the number of protons = The number of electrons = 17

The atomic number of atom, X = The number of protons in X = 17

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.