(a) when the following skeletal equation is balanced under basic conditions, what are the coefficients of the species shown?

Which of the following elements is a representative element? a. chromium (cr) b. aluminum (al) c. mercury (hg) d. silver (ag)

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

Butadiene undergoes a reaction at a certain temperature in the gas phase as follows: 2c4h6(g) --> c8h12(g) the following data were collected for this reaction: time (min) [c4h6] (m) 0 0.36 15 0.30 30 0.25 48 0.19 75 0. determine the order of the reaction and the rate constant. 1st order and k = 4.3x10 -4 s-1 1st order and k = 2.3x10-4 s-1 2nd order and k = 4.3x10-4 s-1 2nd order and k = 2.3x10-4 s-1 zero and k = 4.3x10-4 s-1