A-potassium
B-lead
C-iron
D-magnesium
E-zinc
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The unknown substance : Lead
Given
Density of element
mass of unknown substance = 40 g
volume = 3.5 cm³
Required
The density of unknown substance
Solution
Density is the ratio of mass per unit volume
The unit of density can be expressed in g/cm³ or kg/m³
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
Input the value to find the density of an unknown substance :
ρ = 40 g : 3.5 cm³
ρ = 11.43 g/cm³
If we look at the table, the substance which has a density of 11.43 is Lead