Answer:
Explanation:
<u>1) Data:</u>
a) [OH⁻] = 2.1 × 10⁻⁶ M . . . (the symbol g shown in the question is a typo)
b) pH = ?
<u>2) Formulae:</u>
<u>3) Solution:</u>
- pOH = log ( 1 / 2.1 × 10⁻⁶ ) = 5.7
- pH = 14 - pOH = 14 - 5.7 = 8.3
Molecular formula of sulfur trioxide is SO₃
Molar mass of SO₃ is - 32 + (16 x 3 ) = 80 g/mol
1 mol of any substance consists of 6.022 x 10²³ units. In 1 mol of SO₃ there are 6.022 x 10²³ molecules of SO₃
in 80 g of SO₃ - there are 6.022 x 10²³ molecules of SO₃
Therefore in 78 g of SO₃ - there are 6.022 x 10²³ /80 x 78 = 5.871 x 10²³ SO₃ molecules
True. But it is not entirely fool proof.
We know that the equation for density is:

where D is the density, m is the mass in g, and V is the volume in either mL or cubic centimeters.
So then, given two of the variables, we can solve for density:


Therefore, the density of the bread is 0.6g per cubic centimeter.