In a hydrogen fuel cell, hydrogen gas and oxygen gas are combined to form water. write the balanced chemical equation describing this reaction (using lowest whole-number coefficients.

2H₂ + O₂ → 2H₂O

Explanation:

The problem tells us that hydrogen gas (H₂) and oxygen gas (O₂) are the reactants, while water (H₂O) is the only product. Thus, the reaction is:

H₂ + O₂ → H₂O

In order to balance this equation, we begin with counting the atoms of O present in the left side and in the right side of the equation. Because there are two O atoms in the left but only one on the right, we add a coefficient of 2 in the right side:

H₂ + O₂ → 2H₂O

Now we count the H atoms, there are 2 in the left and 4 in the right, so we add a coefficient of 2 for the hydrogen gas:

2H₂ + O₂ → 2H₂O

Now there are 4 H atoms in both sides, and 2 O atoms in both sides, so the equation is balanced.

conduction is the transfer of thermal energy (heat in transfer) due to collisions between the molecules in the object. collisions between adjacent atoms and molecules transfer kinetic energy from the warmer to the cooler object. the objects must be in physical contact.