Final answer:
After the chemical reaction, the total mass of the sealed glass container setup will still be 950 grams due to the law of conservation of mass.
Step-by-step explanation:
The student's question involves understanding the law of conservation of mass in a chemical reaction. When the chemical in the glass container is ignited and reacts completely, the total mass of the setup will remain the same, which is 950 grams. No matter is lost during the chemical reaction. The mass of the container plus any gaseous substance that may have been produced by the burning chemical, such as carbon dioxide, is accounted for within the sealed system. This means that even if gases are produced, they are still within the container, and thus their mass is included in the total mass of the setup post-reaction.