The hydrogenation of unsaturated hydrocarbons is

an important industrial process. Precious metals,

such as platinum and palladium, can greatly

increase the rate of this reaction. During this

process, the gaseous reactants are pumped

across a layer of metal powder. An example of this

process is shown below.

Describe how the metal probably increases the

reaction rate, identify whether this is an example

of homogeneous or heterogeneous catalysis, and

explain how you know.

Which statement is true about ionic compounds?

If oil spills continue, all of the following should be expected except (2 points) death of aquatic life. polluted groundwater. decreased soil productivity. increased global temperatures.

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.