20. What is the formula for an lanic compound mede of Al and ritregen? A. Al3N2 B. Al2N3 c. AIN D. Ali,Ns E. None of the above. 21. A compound has a formula mass of 6198 amu and is comprised of atoms of sodium end oxygen in a definite ratio. The name of the compound described here is: Show your wark. A. sodium menoxide. B. disodium oxide. C. sodium oxide. D. sodium dioxide. E. sodium(I) oxide: 22. If the mass natio of K to F in a compound is 206i, how mony grems of F are needed to reoct with 45.7g of K ? show your work. A. 0,0211 B. 45.7 C. 941 D. 221 E none of the above 23. Which of the following signs should be prominently disployed in a chemistmy laboratory? THE HOGGINGS GAUII