22. a cubic object has sides with lengths of 6.0 cm,
3.0 cm, and 2.0 cm. the mass of the cube
is 162.2 g. what is its density to the correct
number of significant figures?
(1) 0.22 g/cm3 (3) 4.5 g/cm3
(2) 0.2219 g/cm3 (4) 4.505 g/cm3

option 4 =4.505 g/cm³

Explanation:

Density:

Density is equal to the mass of substance divided by its volume.

Units:

SI unit of density is Kg/m3.

Other units are given below,

g/cm3, g/mL , kg/L

Formula:

D=m/v

D= density

m=mass

V=volume

Symbol:

The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.

Given data:

Mass of cube = 162.2 g

density = ?

Volume =  6cm× 3cm×2cm = 36cm³

Solution:

d= m/v

d = 162.2 g/ 36 cm³

d = 4.505 g/cm³

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm

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