You have a plume of hexavalent chromium as chromate (CrO4 2- ) that will be reduced to insoluble Cr3 . The molecular mass of chromate is 115.9 g/mol. The concentration is 238 ppm in water. How much zero valent iron (ZVI) will you need to add to completely transform the chromium. The ZVI will be converted to Fe2 . The molar mass of iron is 55.9 g/mol.

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

24

(b) which contains higher levels of vitamin b, oranges or spinach?

explanation:

you can eliminate a, c, and d because they are questions based on opinions.

b.false that your answer

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.