What makes the outer shell electrons important is that they a) determine the chemical reactivity of the atom b) are not really important so they can be lost easily c) will always seek out atoms that have the same number of outer shell electrons d) tell you what element you’re dealing with if you only know how many electrons are in the outer shell

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.

Which of the following are sources of revenue for media companies? a. direct sales to producers b. advertising and subscriptions c. online purchase d. capital investments

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks. energy was destroyed inside the blocks. energy was absorbed into the blocks from outside the system. energy was transferred from the warmer block to the cooler block.