A good reaction that gives off a bright light occurs when magnesium is burned in a bunsen burner. As a result, it binds with oxygen in the air. What is the balanced chemical equation for this reaction?
A)
Mg + O → MgO
B)
Mg + O2 → MgO2
C)
2Mg + O → Mg2O
D)
2Mg + O2 → 2MgO

Question

A good reaction that gives off a bright light occurs when magnesium is burned in a bunsen burner. As a result, it binds with oxygen in the air. What is the balanced chemical equation for this reaction?
A)
Mg + O → MgO	
B)
Mg + O2 → MgO2	
C)
2Mg + O → Mg2O	
D)
2Mg + O2 → 2MgO

anonymous · Answer

D as it is balanced.

photon336 · Answer

@WhatTehHeck how do you know which one is balanced or not?

sweetburger · Answer

The process for going about these is that you get your known reactants on one side and your know products on the other side. For this question you have to know that Mg exist by itself in the atmosphere and that Oxygen exist diatomically in the atmosphere as O2. Therefor you will have Mg + O2 ---> MgO. This is your base equation. Oxygen has a common charge of -2 and Magnesium is an alkaline earth metal and has a common charge of +2. When the +2 Mg combines with the -2 O2 it forms MgO which has a net charge of +2 -2 = 0. Now that you understand how this reaction is theoretically possible it now just comes down to getting the correct coefficients to get the proper balanced amount of each material on each side of the equation. For the base reaction Mg + O2 ---? MgO you have |dw:1450305238474:dw|. We need to increase the number of Oxygen on the product side by increasing the coeffiecient in front of the MgO to 2. This now increases the amount of Magnesium on the product side so we must change the coefficient in front of the Mg in the reactant side to 2 as well to balance out the change to the amount of Mg. The final reaction which is balanced that was previously stated is 2Mg + O2 ---> 2MgO.