What is the mass of a bar of aluminum with length 5.3cm, width 0.32 cm and height 2.34cm? The density of aluminum is 2.70g/cm3.

Explanation:

Density of a substance can be found by using the formula

Making mass the subject we have

From the question

Density = 2.70 g/cm³

We assume that the aluminum is a cuboid

and volume of a cuboid is given by

Volume = length × width × height

length = 5.3 cm

width = 0.32 cm

height = 2.34 cm

Volume = 5.3 × 0.32 × 2.34 = 3.97 cm³

Substitute the values into the above and solve for the mass

We have

mass = 2.70 × 3.97

We have the final answer as

Hope this helps you

the grams   of   barium that   are in   2.3 x 10^23   atoms of barium   is   52.4 g (answer c)

    calculation

mass = moles   of ba   x molar   mass of ba

  molar mass of ba from periodic table=   137.3 g/mol

  use the   avogadro's law   constant   to   calculate the moles of barium

  that   is     1 mole =   6.02   x 10^23 atoms

                    ? moles = 2.3 x 10^23   atoms

by cross   multiplication

=(1 mole   x 2.3x 10^23 atoms)   / 6.02   x10^23 atoms)=   0.382   moles

mass   is therefore = 137.3   g/mol x 0.382 mol = 52.4 ( answer c)

explanation: