They all don’t, they also can have positive charges like LiOH (Lithium Hydroxide)
C3H8 + O2 --> CO2(g) + H2O(g) + energy(heat)
butane + oxygen --> carbon dioxide + water + heat
Hydrogen gas(H2) has a molar mass of 2 g. Molar mass of a substance is defined as the mass of 1 mole of that substance. And by 1 mole it is meant a collection of 6.022*10^23 particles of that substance.
So number of moles of H2 are 0.5 in this case. And thus it means there are (6.022*10^23)*0.5 particles( here they are molecules) in 1g of H2.
They are good conductors of heat and electricity.
They are solid at room tempature
They have a high melting point
