More Fun with Moles 1. What is the mass, in grams, of each of the following? a) 1.00 mol lithium b) 6.022x1023 atoms carbon 13. Find the percent metal in each compound: a) sodium chloride b) cobalt (II) chlorate c) barium acetate 2. Determine the mass, in grams of each of the following. a) 3.00 mol aluminum b) 1.38 mol nitrogen 14. A 25.0 g sample of an orange compound contains 6.64 g potassium, 8.84 g chromium and 9.52 g oxygen. Find the empirical formula. 3. How many moles of each substance are represented by the following? a) 11.5 g sodium b) 4.5x10-12 g oxygen 15. When 5.0 g of ethanol is burned, 2.61 g of carbon, 0.657 g hydrogen and 1.73 g oxygen are released. What is the empirical formula for ethanol? If ethanol’s molar mass is 46 g, what is the molecular formula? 4. How many moles are equal to a) 2.25x1025 atoms zinc b) 52,000,000 atoms neon 5. How many atoms are in each of the following: a) 1.5 mol sodium b) 0.25 mol chlorine 6. What is the mass, in grams, of a) 4.5x1012 atoms chlorine b) 8.42x1018 atoms bromine 7. How many atoms are in: a) 5.4 g nitrogen b) 1.5 g potassium 8. Which element in each pair contains the most atoms? a) 0.5 mol carbon or 0.75 mol lithium b) 0.25 mol silicon or 10 g chlorine c) 15.0 g calcium or 40.0 g silver 9. Name these ionic compounds: a) TiSO3 b) Bi3(PO4)2 c) Fe(MnO4)2 d) HgS e) SnO2 f) PbCO3 10. How many grams of oxygen has the same number of atoms as 12 g aluminum? 11. If 4.75x1023 atoms of silver are placed on a balance. How many atoms of gold would have the same mass? 12. A garnet has the chemical formula Fe3Al2(SiO4)3. How many moles of each element are present in five moles of garnet? 16. Vitamin C contains 40.91% carbon, 4.59% hydrogen and 54.50% oxygen. If vitamin C’s molar mass is 180 g/mol, what is the molecular formula? 17. Name these covalent compounds: a) OF2 b) PF3 c) XeF4 d) N2O e) N2F2 18. Write formulas for these ionic compounds: a) tin (IV) carbonate b) lead (II) chlorate c) aluminum peroxide d) cesium hydrogen sulfate 19. Determine the empirical formula of the comound that is 43.2% by mass K, 39.1% Cl and also contains oxygen. Name this ionic compound. 20. Determine the empirical formula for a compound if an 83.45 g sample contains 22.03 g sodium, 30.71 g sulfur and the rest oxygen. If the molar mass of this compound is 174.12, what is the molecular formula?