Which compound contains both ionic and covalent bonds?
(1) ammonia
(2) methane
(3) sodium nitrate
(4) potassium chloride

The alkali metals (group 1) consist of lithium (3), sodium (11), potassium (19), rubidium (37), cesium (55), and francium (87). they are soft, metallic solids with low densities and low melting points. based on the data shown in figure 1, how many valence electrons do alkali metals share?

What are the primary responsibilities of a chemical engineer involved in "r& d"? develop large scale manufacturing operations discover new products and processes training of new chemists determine products needed by consumers

Which position represents spring in the southern hemisphere? a) b) c) d)