Using formation values, calculate the H rxn for the combustion of 3 moles of methane (CH4). Write a balanced chemical equation. CH4= -74.81 kj/mol

CO2= -393.51 kj/mol

H2O= -285.83 kj/mol

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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.

An atomic nucleus is composed ofa)protons.b)protons and neutrons.c)protons and electrons.d)protons, neutrons, and electrons.

Which of the following is in the lanthanide family? a) uranium b) promethium c) silver d) gold