Single displacement and combustion reactions are ALWAYS redox.
Zinc is a metal. At STP, it exists as solid and is stable as it is. It is an important mineral and is used in many applications like in food, metal and drugs. Zinc can be found in the Earth's crust and also it is present in small amounts in some food.
Even though two grams seemed to disappear or vanish, the law of conversation of mass still holding true. Mercuric oxide, when heated, forms a gas of mercury and oxygen. During the investigation, some gas could have escaped or evaporated.
In order to balance this equation you need to count each element and how many of the individual elements are in the equation.
_H2+N2=2 NH3
You multiply the 2 (Which is the coefficient) by the 3 (which is the subscript) This would equal 6 which indicated there are 6 hydrogen atoms on the right side so the left side should also have 6 hydrogen atoms
The missing coefficient on the left side must multiple the 2 to become 6 hydrogen
Answer=3
