The rate at which a substance passes through a semipermeable membrane is determined by the diffusivity d cm2/s of the gas. d varies with the membrane temperature t k according to the arrhenius equation: d d0 exp e/rt where d0 the preexponential f actor e the activation energy for diffusion r 1: 987 cal/ mol k diffusivities of so2 in a fluorosilicone rubber tube are measured at several temperatures, with the following results: t k d cm2/s 106 347.0 1.34 so that d 1: 34 106 cm2/s 374.2 2.50 396.2 4.55 420.7 8.52 447.7 14.07 471.2 19.99 (a) what are the units of d0 and e? (b) how should the data be plotted to obtain a straight line on rectangular coordinates? (c) plot the data in the manner indicated in part (b), and determine d0 and e from the resulting line. (d) repeat part (c) using a spreadsheet program.

in theory, limestone is composed principally of the compound calcium carbonate - caco3, but in reality this compound is deposited in conditions involving a number of other compounds as impurities so it ends up being a mixture of many compounds.

hope this : -)

tony (lordcaos066)

b. acid is the correct answer @jayxboof all social media

acid : acids are those which accepts an electron-pairs.

base : bases are those which donates ab electron-pairs.

alkali : it is a base that dissolves in water. it is basically a base and the ph greater than 7.

hydroxide ion : it is a poly-atomic ion which is negatively charged.

the major pests we deal with are insects, weeds and fungal diseases. a pesticide is a product, whether organic or chemical, used to kill the target pest. there are other techniques gardeners should use that can prevent the severe infestations that make the use of pesticides necessary