Question

In the equation

2H2+1O2→→2H2O

if you change the 2H2
to 3H2
molecules and balance the equation, identify which statement is correct?

(1 point)
Responses

The equation will produce three molecules of water.
The equation will produce three molecules of water.

It is not possible to produce water without leftover molecules.
It is not possible to produce water without leftover molecules.

The result of the equation will be the same.
The result of the equation will be the same.

Each oxygen molecule will combine with 2 hydrogen molecules with no leftover molecules.

Answer 1

"It is not possible to produce water without leftover molecules."

Explanation: The reaction needs 2 H2 per O2. With 3 H2 you would need 1.5 O2 to make 3 H2O (a fractional molecule), or if you only have whole O2 molecules (1 O2) you'd make 2 H2O and have 1 H2 leftover. To avoid fractions and leftovers you must scale up to whole-number coefficients (e.g. 6 H2 + 3 O2 → 6 H2O).