How many hydrogen atoms in the
molecule (NH4)2C8H402?

12 hydrogen atoms

Explanation:

Let's consider the chemical formula of the compound (NH₄)₂C₈H₄O₂.

We can see the ammonium ion, NH₄⁺, which contains 4 hydrogen atoms. However, this ion is enclosed in parenthesis with a subindex 2. That means that we have to multiply the whole ion by 2, therefore resulting in 8 atoms of hydrogen. Then, in C₈H₄O₂, we can see another 4 hydrogen atoms. The total number of hydrogen atoms in 1 molecule of (NH₄)₂C₈H₄O₂ is 8 + 4 = 12 hydrogen atoms.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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