All of them! (technically speaking) Hydrogen is the most abondent element in the universe so it's practically everywhere.
united states
There are 196 countries.
There are 257 countries in the world.
There are 195 countries in the world.
There are 257 countries in the world.
There are many countries in the world, a country cannot contain the world.
There are 195 countries in the world today.
There are approximately 195 countries in our world.
There were 195 countries in the world in 2015.
There are 195 countries in the world today.
There are 193 countries in the world and there are 7 continents in the world.
Currently, the greatest world producer of hydrogen is China. China's hydrogen production is driven by its growing demand for clean energy and efforts to reduce greenhouse gas emissions. However, other countries like Japan, the United States, and Germany are also major producers of hydrogen.