- A compound has the empirical formula CH2O and a formula mass of 120.10 amu.
What is the molecular formula of the compound?
- How many grams of NaOH are in 500.0 mL of 2.65 M NaOH solution?
- A.53.0 g
- B.5.30 x 102 g
- C.0.0189 g
- D.1.33 g
- Determine the percentage of calcium ion in Ca3(PO4)2 .
- A compound of carbon and hydrogen contains 92.3% C and has a molar mass of 78.1 g/mol. Select all that is correct.
- A.The empirical formula is CH.
- B.The molecular formula is C8H8.
- C.The molecular formula is C6H6.
- D.There is not enough information for us to determine the molecular and the empirical formulas.
- What is the percentage by mass of O in Cu4(AsO3)2(CH3CO2)2?
- A 250-mL sample of 1.25 M NaOH solution is prepared by dissolving an amount of 5.28 M NaOH. Select all that is correct.
- A.59.2 mL of the 5.28 M NaOH was used in the dilution.
- B.The moles of NaOH transferred from the 5.28 M NaOH solution are equal to the number of moles in the 250-mL sample of the NaOH solution.
- C.-There are fewer moles of NaOH in the dilute solution than in the amount of the concentrated solution used.
- D.1.69 x 10-2 mL
- What is the molar concentration of sodium ions in 0.652 M sodium sulfate solution?
- A.0.652 M
- B.1.30 M
- C.0.326 M
- D.0.767 M
- A sample of pure copper has a mass of 16.35 g. How many moles does this mass correspond to?
- A.3.887 mol
- B.1.549 x 1023 mol
- C.0.2573 mol
- D.2.715 x 10-23 mol
- Which sample contains the greatest number of atoms?
- A.25 g Cu
- B.25 g F2
- C.25 g Ne
- D.25 g Ba
- If a compound has a ratio of one nitrogen to two hydrogen, what is the percentage of nitrogen in the compound?