Moles Conversion Language

A mass of 100g of NaCl has how many moles of NaCl? Which is the first step in finding the answer?

• 58.44g NaCl/100g

• 100g/58.44g NaCl

• 100g x 6.02 x 10²³

• (1.71 mol) x (6.02 x 10²³)

A sample of SO₄ contains 7.826 x 10²³ atoms. The mass of the sample is 124.89 g. Which one is the correct solution to find the answer?

• A. (7.826 x 10²³) (6.02 x 10²³)

• B. 7.826 x 10²³

  6.02 x 10²³

• C. (1.3 mol SO4) x (96.07g/mol)

• first step: B

  second step: C

• first step: A

  second step: C

The molar mass of NO₂ is 46.01g. How many moles of NO₂ are present in the 110.15 g sample? Which is the step to find the answer?

• __110.15 g___

   46.01 g/mol NO₄

• 46.01 g/mol NO₂

  110.15 g

• 2.39 mol x 6.02 x 10²³

How many grams are needed to have 3.25 mol of PO₄? Which are the correct steps to follow, and what is the correct answer?

• grams to moles: molar mass PO₄ x 3.25 mol

• moles to grams: 3.25 mol x molar mass of PO₄

• grams to moles: 3.25 mol x 6.02 x 10²³

• 94.97g/mol PO₄

  3.25 mol

How many molecules are there in 15 moles of methane gas, CH₄?

Which is the correct conversion step?

• moles to molecules

• moles to atoms

• molecules to grams

• molecules to moles

Each pure substance listed in the periodic table has ONE mole equivalent to 6.02 x 10²³ atoms. Which is the pair that has the correct name and example?

• particle: matter

• element: antimony(Sb)

• molecule: water(H₂O)

• compound: NaCl

Tags

NGSS.MS-PS1-1

What is the correct unit for the formula/molecular mass of a compound?

• g/mol

• atomic mass unit(amu)

• grams

• mol/g

The sum of the atomic masses of each atom in formula unit. It is expressed in grams per one mole of a substance.

• formula mass

• molecular mass

• molar mass

• Avogadro's number

Tags

NGSS.HS-PS1-7

One mole of potassium is equal to

• 39.10 molecules

• 39.10g/mol

• 6.02 x 10²³ atoms

• 6.02 x 10²³ molecules

A sample of lead contains 3.01 x 10²³ atoms. Find the mass of the sample. Which pair represent the given information and unknown quantity?

• given: 3.01 x 10²³

  find: mass in grams of Pb

• given: 3.01 x 10²³

  find: molar mass of Pb

• given: one mole of Pb

  find: number of atoms of Pb

• given: 6.02 x 10²³

  find: mole of Pb