What is the smallest particle of an element that has the chemical properties of that element

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.

Which of the following units is not an official si unit

How many liters of ethylene glycol antifreeze (c2h6o2), with a density of 1.100 g/l, would you add to your car radiator containing 15.0 kg of water if you needed to protect your engine to - 21.5°c? for water, kf = 1.86°c m -1.