Give the major product formed when phenol is heated with concentrated H2SO4 and SO3. (There is more than one correct answer, but draw just one.)

See image attached and explanation

Explanation:

The reaction of phenol with SO3/H2SO4 is an electrophilic reaction. The electrophile attacks portions of high electron density in the substrate phenol.

The -OH group activates phenol towards electrophilic substitution at the ortho and para positions, hence the product(s) formed in this reaction(only one product is shown here as required by the question).

The sulphonation of phenol using concentrated sulfuric acid at lower temperature yields majorly the ortho product whereas at higher temperature the para product predominates.

1.21 g of Tris

Explanation:

Our solution if made of a solute named Tris

Molecular weight of Tris is 121 g/mol

[Tris] = 100 mM

This is the concentration of solution:

(100 mmoles of Tris in 1 mL of solution) . 1000

Notice that mM = M . 1000  We convert from mM to M

100 mM . 1 M / 1000 mM = 0.1 M

M = molarity (moles of solute in 1 L of solution, or mmoles of solute in 1 mL of solution). Let's determine the mmoles of Tris

0.1 M = mmoles of Tris / 100 mL

mmoles of Tris = 100 mL . 0.1 M → 10 mmoles

We convert mmoles to moles → 10 mmol . 1mol / 1000mmoles = 0.010 mol

And now we determine the mass of solute, by molecular weight

0.010 mol . 121 g /mol = 1.21 g