Final answer:
The density of the unknown substance with a mass of 25 grams and a volume of 4 cm³ is calculated using the density formula and is found to be 6.25 g/cm³.
Step-by-step explanation:
To find the density of an unknown substance we use the formula:
Density (D) = Mass (m) ÷ Volume (V).
Given the mass of the substance is 25 grams and its volume is 4 cm³, we can plug these values into the formula:
Density = 25 g ÷ 4 cm³ = 6.25 g/cm³.
Therefore, the density of the unknown substance is 6.25 g/cm³, which indicates that it is a very dense substance, likely to be a solid rather than a liquid or gas.