science - density

When calculating density use the GRESS method.
G (given): mass (M)
                   volume (V)

R (required): density (D)?

E (equation) D=M/V

S (solution): D=M/V
                       D=x/y
                       D=z

S (statement) the density if am object with a mass of xg and a volume of y ml is z g/ml

D=M÷V
M= D x V
V= M÷D

K6: sulfuric acid is used in mainly industrial processes.  If concentrated sulfuric acid has a density of 1.94g/ml, what is the mass of a 26.2ml sample (use GRESS)

G: D 1.94g/ml
     V 26.2 ml
R: M
E: M= DxV
S:  M= 26.2 x 1.94
     M=50.828
S the mass of the sulfuric acid is 50.828 g

K7: an irregular object with a mass of 18kg displaces 2.5L of water when placed in a large overflow container.  Calculate the density.
G: M/V
M18kg
V2.5L
R: D
E: D=M/V
S: D=18kg ÷ 2.5
     D=7.2
S: the density of the object is 7.2 kg/l

K8: a graduated cylinder has a mass of 80g when empty.  When 20 ml of water is added, the cylinder has a volume 100g.  If a stone is added to the cylinder, the water level rises 45ml and the total mass is now 155g.  What is the density of the stone.
M=100-80
M=20
G: M÷V
Given is 20÷45
R: D
E: D=M÷V
E: D= 20÷45
 S:  D =0.44
S: the density of the stone is 0.44 g/ml