A type of element that tends to lose electrons when they bond with other atoms is called _____ ?

Elements are the purest form of substances and cannot be further sub-divided into non-identical constituents (assuming no isotopes), unlike compounds and mixtures. Elements can be classified according to their tendency to lose electrons, gain electrons, or share electrons. The elements that generally tend to lose electrons when making bonds with other elements are called cations. These are frequently metals. Anions, on the other hand, like to accept electrons when making bonds with other elements. 

The ions of metals that are formed after losing the electron(s) are known as cations, while non-metallic ions—formed after gaining electron(s)—are called anions. Thus, Na+ is a cation and Cl- is an anion.

Some examples of metals include, sodium, calcium, magnesium, lithium, potassium, etc. Among these, sodium tends to lose 1 electron and becomes sodium ion (Na+) and can easily react with chloride (Cl-, an ion of chlorine, a non-metal) to form NaCl. Similarly, a calcium atom tends to lose 2 electrons when bonding with two chlorine atoms to form a molecule of CaCl2.

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