Calcium oxide, CaO, reacts with carbon in the form of graphite. Calcium carbide, CaC2, and carbon monoxide, CO, are produced in an endothermic reaction. CaO(s) + 3C(s) + 462.3 kJ → CaC2(s) + CO(g)

If 1.38 × 1024 molecules of calcium oxide react with excess graphite. How much energy is needed?

1) these are barrel shaped microtubules in most animal cells, that organize the spindles during cell division

For each of the compounds below, show that the charges on the ions add up to zero. a. kbr b. cao c. li(2)o d. cacl(2) e. alcl(3)

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.