You are asked to build some models of methane molecules for a science fair. You will arrange your model atoms as shown on the right, but you will use ping-pong balls and tennis balls to model hydrogen atoms and carbon atoms. If you have 12 ping-pong balls, how many tennis balls will you need? Use the model you just developed to justify your answer.

‘which reaction would most likely require the use of an inert electrode?

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.

Condensation happens when water vapor cools. true or false? ?