What volume of a product is required to make half liter of 0.25% of the product solution?

0.00125 liters of product

Explanation:

So the question it tell you that 0.25 % from 0.5 liters is pure product.

So we calculate the volume of pure product:

volume = (0.25 / 100) × 0.5 = 0.00125 liters

Now to produce the solution over 0.00125 liters of pure product you add (most likely) water until you reach a volume of 0.5 liters.

your picture is not part of the scientific method.

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