Calculate the mass of naphthalene required to react stoichiometrically with the moles of 2-bromo-2-methylpropane that you have placed in the flask. Dispense that quantity of naphthalene into the weighing dish. There is some imprecision in delivering the powder onto the weigh boat, but a mass within 0.040 g of the calculated stoichiometric quantity will be sufficient for this experiment. Note that you can use a combination of the 1 g and the 0.1 g buttons to add the required mass. If you overshoot the goal, you can discard the weighing boat and get a new one. RECord the sample mass dispensed below. mass of naphthalene (g)

The reaction of 2-bromo-2-methylpropane and naphthalene is stoichiometrically  in a mole ratio of 1:1.

Notice that in the question, the moles of 2-bromo-2-methylpropane placed in th flask wasn't mentioned. if I assume that it was 1.24 moles then;

1 mole of naphthalene reacts with 1 mole of 2-bromo-2-methylpropane

x moles of naphthalene reacts with 1.24 mole of 2-bromo-2-methylpropane

x = 1 * 1.24/1

= 1.24 moles of naphthalene

Molar mass of naphthalene  = 128.2 g/mol

Mass of naphthalene  = 128.2 g/mol * 1.24 moles of naphthalene

Mass of naphthalene  =159 g

For more about how to solve stoichiometry problems:

some of the qualities most frequently associated with the baroque are grandeur, sensuous richness, drama, vitality, movement, tension, emotional exuberance, and a tendency to blur distinctions between the various arts.

answer: c.

explanation: