What is the percent composition of hydrogen in a compound if the mass of the initial compound is 276 gram and the mass of collected hydrogen after decomposition is 41.4 grams?

What is the most stable monatomic ion formed from nitrogen

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.

The identities of substances are the same before and after which type of change