How much hydrogen is used in space suits as thrust?

The thrusters made so far for use by suited astronauts have used either compressed oxygen (not really a good choice, just a convenience) , compressed nitrogen, or hydrogen peroxide (decomposed into steam). read more

Google: "Density of hydrogen in interstellar space" The actual density of hydrogen as it exist in interstellar space is on the average of about 1 atom per cubic centimeter. In the extremes, as low as 0.1 atom per cubic centimeter has been found in the space between the spiral arms and as high as 1000 atoms per cubic centimeter are known to exist near the galactic core. read more

See also Liquid Hydrogen as a Propulsion Fuel, 1945-1959, the NASA History Office's detailed account of liquid hydrogen as a propulsion fuel in the early days of space flight. read more