What is the difference between alchemy and science

alcemary: the forerunner of chemistry, concerned with the transmutation of matter, with attempts to convert base metals into gold or find a universal elixir.

science: the intellectual and practical activity encompassing the systematic study of structure and behaviour of physical and natural world through observation and experiment.

the major pests we deal with are insects, weeds and fungal diseases. a pesticide is a product, whether organic or chemical, used to kill the target pest. there are other techniques gardeners should use that can prevent the severe infestations that make the use of pesticides necessary

the answer is na (sodium)