Let mb=mass of empty bottle, mw=mass of water only and
ma= mass of alcohol only
given; mb=19g mb + mw = 66g mb + ma = ? R.d=0.8 R.d=mass of alcohol
⇒massofalcoholmassofequalvolumeofwater
⇒ mass of equal volume of water = mw=66-19=47g ⇒0.8 = ma47 ⇒ma=0.8×47 =37.6g ; mb + ma = 19+37.6=56.6g
