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Which element has the lowest electronegativity? calcium(ca) gallium(ga) selenium(se) bromine(br)

Water undergoes a large change in density at 0 ∘ c as it freezes to form ice. calculate the percent change in density that occurs when liquid water freezes to ice at 0 ∘ c given that

Ineed this awnser fast select the correct answer. this chemical equation represents the burning of methane, but the equation is incomplete. what is the missing coefficient in both the reactants and the products? ch4 + → co2 + a. 0 b. 1c. 2d. 3 e. 4