Massiel

If the BOD5 of a waste is 220 mg/L and the ultimate BOD is 320 mg/L, what is the rate constant?

One reaction that destroys O3 molecules in the stratosphere is NO + O3  NO2 + O2 When this reaction was studied in the laboratory, it was found to be first order with respect to both NO and O3 with a rate constant of 1.9 x 104 mol L-1S-1. If [NO] = 1.2 x...

The activation energy for the reaction in which CO2 decomposes to CO and a free radical oxygen atom, O, has activation energy of 460 kJ mol^-2. The frequency factor is 2 x 1011 s^-1. What is the rate constant for this reaction at 298 K?

If in August 1911 Mme. Curie prepared an international standard containing 20.00 mg of RaCl2, what will the radium content of this standard be in August 2010?

A sound power level reading of 127 dB was taken near a construction site where chippers were being used. When all but one of the chippers stopped working, the sound power level reading was 120 dB. Estimate the number of chippers in operation when the read...

The half live of Iodine-131 is 8 days. if you started out with 40 mg sample of iodine-131, then what would be the mass of the sample after 32 days? please show your work

I got it!!! the answer is 4.6x10^-6

Thanks!

thanks!

My daughter had the same problem today... The probability is 1/3... If its a fair game then all of the factors have equal opportunity to occur.