Calculate the number of moles of NaOH (sodium hydroxide, an ingredient in drain cleaners and oven cleaners) in a 10.0 g sample of this substance.

Question

Quizplus · Accepted Answer

To calculate the number of moles of NaOH in a 10.0 g sample, we need to use the molar mass of NaOH and the formula:

moles = mass/molar mass

The molar mass of NaOH is 40.00 g/mol (1 x 22.99 g/mol for Na + 1 x 15.99 g/mol for O + 1 x 1.01 g/mol for H). Therefore:

moles = 10.0 g / 40.00 g/mol = 0.250 mole

The best choice is E, which gives the correct answer.

Calculate the Number of Moles of NaOH (Sodium Hydroxide, an Ingredient