An atom of a certain element has 18 protons, 18 electrons, and a mass number of 40. At room temperature this element is a very stable gas. How many
neutrons are in this atom?
Record your answer and fill in the bubbles on your answer document. Be sure
to use the correct place value.

Patricia is told by her physician that her body and brain chemistry have physically adapted to the drug and that she has become dependent on the tranquilizers prescribed for her by another doctor.

2. if scientists identify an animal with bilateral symmetry and no segmentation, which phylum can it definitely not belong to? a. roundworms b. annelids c. mollusks d. flatworms

You have been asked to lead a demonstration for the undergraduate microbiology lab course about the uses of negative staining when studying bacteria. a "negative" stain does not stain the bacterial cell itself but stains the space between cells. under magnification, the acidic (negativelycharged) nature of the stain will be repelled by the negatively charged bacterial cell wall and willleave the cell colorless in a stained background. negative stains are used primarily to reveal the presence of negatively charged bacterial capsules; therefore, they are also called capsule stains. encapsulated cells appear to have a halo surrounding them. the negative stain procedure does not require heat fixation, which limits any chances of alteration in bacterial cell shape and size. the bacterial suspension is added to a drop of stain, such as nigrosin or eosin, and drawn across the glass slide using a coverslip.nigrosin staining-not safranin staining-of klebsiella pneumoniae will allow for the visualization of the cell shape and the determination of the presence of a capsule.true/false