A chemist adds of a M sodium carbonate solution to a reaction flask. Calculate the millimoles of sodium carbonate the chemist has added to the flask. Round your answer to significant digits.

256 milimoles of Sodium Carbonate are in the flask

Explanation:

The chemist adds 180mL of a 1.42M sodium carbonate solution.

Molarity is an unit of concentration in chemistry defined as the ratio between moles of solute (Sodium Carbonate, in this case) per liter of solution.

A 1.42M solution contains 1.42 moles of Sodium carbonate in 1L of the solution.

As you have 180mL = 0.180L, moles of sodium carbonate you have are:

0.180L × (1.42 moles Sodium Carbonate / 1L) = 0.2556 moles of sodium carbonate

1000milimoles are equal to 1mole. 0.2556 moles are:

0.2556 moles × (1000 milimoles / 1 mole) =