Cmon bro you better then this
<u>Answer:</u>
<em>Silver tarnishing as the silver metal reacts with sulphur is a chemical change.</em>
<u>Explanation:</u>
Tarnishing is the process of chemical change occurring on the surface of objects leading to corrosion or other defects on the surface. The remaining options like dilution, eroding is a physical change where the concentration of salt and rock particles will be decreased, respectively.
Similarly for soil drying also the concentration of water will be decreased leading to a physical change from wetty or dry soil.
But the last option which indicates tarnishing of silver metal on reaction with sulphur is a chemical process as the surface of silver metal will be reacting to sulphur and leads to lose of electrons which leads to corrosion of the surface or tarnishing of silver.
Answer: Bacterial species where observed Typical number on cell Distribution on cell surface
Escherichia coli (common pili or Type 1 fimbriae) 100-200 uniform
Neisseria gonorrhoeae 100-200 uniform
Streptococcus pyogenes (fimbriae plus the M-protein) ? uniform
Pseudomonas aeruginosa 10-20 polar
Explanation:
Pili are structures that extend from the surface of some bacterial cells.
These are hollow, non-helical, filamentous appendages.
Hope it helps you
