Which of the following is evidence that matter is too small to be seen without magnification? aFeeling the heat come off the flames of a fire
bFeeling the grains of salt in between your fingers
cWatching salt disappear when it dissolves in water
dWatching rain fall from the sky during a thunderstorm

Frictional forces acting on an object are often converted into energy, which causes the temperature of the object to rise slightly.

Why do cells appear different in distilled water than they do in 10% salt water?

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.