Elements that easily lose electrons to form positive ions are called metals. This is because they have a low ionization energy, meaning it takes relatively little energy to remove an electron from their outer shell.

Here are some characteristics of metals:

* Low ionization energy: This means they readily lose electrons to become positively charged ions (cations).

* Low electronegativity: This means they have a weak attraction for electrons.

* Good conductors of heat and electricity: Due to the ease with which electrons can move within their structures.

* Malleable and ductile: They can be shaped and drawn into wires.

* Shiny and lustrous: They reflect light well.

Examples of metals that easily lose electrons:

* Group 1 (Alkali metals): Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr). These elements have only one valence electron, which they readily lose to form +1 ions.

* Group 2 (Alkaline Earth Metals): Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra). These elements have two valence electrons, which they readily lose to form +2 ions.

* Transition Metals: Many transition metals also readily lose electrons to form ions, but their charges can vary depending on the specific element and its chemical environment. Examples include Iron (Fe), Copper (Cu), Zinc (Zn), and Gold (Au).

It's important to remember that the tendency to lose electrons is not absolute. Even within a group, the reactivity of metals can vary depending on factors like atomic size and nuclear charge.