In this reaction, how many hydrogen atoms combine into one helium atom How many countries are involved in the International Thermonuclear Experimental Reactor project?

In the fusion reaction that combines hydrogen into helium, three hydrogen nuclei (protons) generally come together to form one helium nucleus. Therefore, the answer to the first question is 3.

Regarding the International Thermonuclear Experimental Reactor (ITER) project, there are 35 countries involved. This collaborative effort aims to demonstrate the feasibility of nuclear fusion as a large-scale and carbon-free source of energy.

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