Respuesta :

Answer:

The mass of 0.280 mole sample of sodium hydroxide NaOH​ is 11.2 grams.

Explanation:

To know the mass in grams of 0.280 moles of sample of sodium hydroxide NaOH, you must know the molar mass of the compound, that is, the mass of one mole of a substance, which can be an element or a compound.

So you know:

  • Na: 23 g/mole
  • O: 16 g/mole
  • H: 1 g/mole

So, the molar mass of NaOH is:

NaOH= 23 g/mole + 16 g/mole+ 1 g/mole= 40 g/mole

Then the following rule of three can be applied: if in 1 mole of sodium hydroxide there are 40 grams, in 0.280 moles how much mass is there?

[tex]mass=\frac{0.28 moles*40 grams}{1 mole}[/tex]

mass= 11.2 grams

The mass of 0.280 mole sample of sodium hydroxide NaOH​ is 11.2 grams.