The filament in an incandescent light bulb is made from tungsten metal (rho = 19.3 g/cm3) that has been drawn into a very thin wire. the diameter of the wire is difficult to measure directly, so it is sometimes estimated by measuring the mass of a fixed length of wire. if a 0.200 m length of tungsten wire weighs 42.9 mg, then what is the diameter of the wire? express your answer in millimetres.

Chromosome 17 is made of over million base pairs.

Phosphoric acid is a triprotic acid ( =6.9×10−3 , =6.2×10−8 , and =4.8×10−13 ). to find the ph of a buffer composed of h2po−4(aq) and hpo2−4(aq) , which p value should be used in the henderson–hasselbalch equation? p k a1 = 2.16 p k a2 = 7.21 p k a3 = 12.32 calculate the ph of a buffer solution obtained by dissolving 18.0 18.0 g of kh2po4(s) kh 2 po 4 ( s ) and 33.0 33.0 g of na2hpo4(s) na 2 hpo 4 ( s ) in water and then diluting to 1.00 l.

How many grams are in 68.2 molecules of br2?