Asolution of ethanol (c2h5oh) in water is prepared by dissolving 75.0 ml of ethanol (density 0.79 g/cm3 ) in enough water to make 250.0 ml of solution. what is the molarity of the ethanol in this solution?

Given the density of ethanol = 0.79

Volume of ethanol = 75.0 mL

Calculating the mass if ethanol from density and volume:

Molar mass of ethanol = (2*atomic weight of C)+(6*atomic weight of H)+(1*atomic weight of O)

                                     =(2*12g.mol) + (6*1g/mol) + (1*16g/mol)

                                     =46g/mol

Moles of ethanol =

Volume of the solution = 250.0 mL

Converting the volume from mL ot L:

Molarity of ethanol in the solution =

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3