Which of the following will lower the rate of reaction? (there are 2 answers to select) A. decreasing the temperature from 30 degrees to 20 degrees Celsius.

B. Adding an enzyme to the reaction.

C. breaking a chunk of reactant up into smaller pieces.

D. decreasing the concentration of a reactant.

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.

What three things does a balanced equation show you?

What is the correct lewis dot structure for arsenic?