Sooo i suck at science like a lot . even tho i have a 70.can someone help me pls?

Compare and contrast physical changes with chemical changes.

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.

Vi limitens. vastery test select the correct answer. which statement explains why large atoms are more reactive than small atoms? a. large atoms have valence electrons farther from the nucleus and lose them more readily. b. large atoms have greater ionization energy, which they can utilize during a reaction. c. large atoms have a greater number of electrons that they can lose during a reaction. d. large atoms have more energy levels, so they have more energy to pass on in a reaction. reset next