Changing in boiling point is directly proportional to the a) molarity of solution b) percent by volume of solution c) molarity of solution d) percent of solution

Consider this initial-rate data at a certain temperature for the reaction described by

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

1) which of the following is the best example of a physical change? a) sugar dissolving in tea b) firefly glowing 2) in the combustion of ethane, what is/are the reactants? c2h6 + o2 ==> co2 + h2o a) c2h6 and o2 b) co2 and c2h6