Well cars need gas to run on if the car does not have gas it wont run and you cant get to places you need to go only if you have gas.
Sodium has an atomic number 11, it means there are 11 electrons in sodium atom and has a net charge zero what when it combines with chlorine it loses one electron and get charge of +1. when and atom loses an electron it gets positive charge and when atom gains electron it gets negative charge. chlorine makes an anion and sodium makes cation and they are oppositely charged so they react with each other.
Both mass and matter both are both properties of an object. However, mass is a way of measuring the weight of an object, while matter is simply the object itself.