An atom, which is the fundamental unit of an element, contains an equal number of electrons and protons.

Here is the generic procedure. This means that each chlorine atom has 17 protons and therefore must also have 17 electrons. Let’s take a picture from google so you can see what i am talking about since i am not sure about the english terms of the numbers.

Adding or removing a neutron from an atom's nucleus creates isotopes of a particular element. Name: Chlorine: Symbol: Cl Atomic Number: 17: Atomic Mass: 35.453 atomic mass units: Number of Protons: 17: Number of Neutrons: 18: Number of Electrons: 17: Melting Point The number of neutrons is calculated by subtracting the atomic number from the mass number. Step 1: For the number of protons, it is equal to the atomic number. The nucleus of an atom contains protons and neutrons.

The chemical element chlorine has 17 electrons, 17 protons and 18 neutrons. Chlorine. The number of neutrons depends on the isotope considered. So in periodic table you have every element presented like this. So in chlorine, we can see that the atomic number is 17. An atom of chlorine-35 contains 18 neutrons (17 protons + 18 neutrons = 35 particles in the nucleus) while an atom of chlorine-37 contains 20 neutrons (17 protons + 20 neutrons = 37 particles in the nucleus). Chlorine atom has 17 protons and 17 electrons. The neutron number however are, 6, 7, and 8, respectively, in each of these Carbon isotopes. You can look up the atomic number for any element on the Periodic Table of the Elements, or any Table of the Elements. Name: Chlorine Symbol: Cl Atomic Number: 17 Atomic Mass: 35.4527 amu Melting Point:-100.98 °C (172.17 K, -149.764 °F) Boiling Point:-34.6 °C (238.55 K, -30.279997 °F) Number of Protons/Electrons: 17 Number of Neutrons: 18 Classification: Halogen Crystal Structure: Orthorhombic Density @ 293 K: 3.214 g/cm 3 Color: green Atomic Structure The number of protons in an element is always the same as the atomic number, which is 17 in this case.