He hows everyone doing?

Use the standard enthalpies of formation for the reactants and products to solve for the δhrxn for the following reaction. (the δhf of c2h4 is 52.26 kj/mol, co2 is -393.509 kj/mol, and h2o is -241.818 kj.) c2h4 (g) + 3o2(g) 2co2 (g) + 2h2o(g) δhrxn = the reaction is .

Apiece of metal with a length of 1.42 cm was measured using four different instruments. which of the following measurements is the most accurate?

Which of the following is not one of the steps in the scientific method a. hypothesize b. summarize c. analyze d. familiarize