3. What substance in the cigarette smoke caused the cotton wool to change
4. What part of the body was represented by the cotton wool
3. What does this experimentell you about the effect of cigarette smoke on the lungat

Which is the layer underground where all empty spaces are filled with a combination of air and water ?

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?

11. phosphorus-32 is radioactive and has a half life of 14 days. how much of a 124 mg sample of phosphorus-32 is present after 56 days? a) 7.75 mg b) 15.5 mg c) 31.0 mg d) 62.0 mg