Chlorophyll a is one of the green pigments found in plants. Chlorophyll a has the molecular formula C55H72MgN4O5. How many atoms are in this molecule?

A-136

B-137

C-138

what is the drag force acting on a car with a resultant force of 600N when the engine is pushing it with a force of 11,000N

Convert 813 torr to kPa

Compounds both and mixtures Choices: (Made of elements) (chemically combined) (fixed proportions) (components change properties) (variable proportions) (2 or more components) (physically combined) (components retain properties)

How many milliliters of 2.55 M NaOH is needed to make 125 mL of 0.75 M NaOH?

Use Boyle's, Charles's, or Gay-Lussac's law to calculate the missing value in each of the following. (a) V1 = 2.0 L, P1 = 0.62 atm, V2 = 1.0 L, P2 = ? atm (b) V1 = 230 mL, T1 = ?, V2 = 400. mL, T2 = 298 K K (c) V1 = 0.55 L, P1 = 740 mm Hg, V2 = 0.

An atom of oxygen (atomic number 8) with an atomic mass of 16 would have how many neutrons?

Chlorophyll reflects which of these colors? a. red b. blue c. green d. yellow

Extracting oil from shale deposits a has been initiated on a large scale in the United States and will soon surpass Canada's production. b involves removing and refining waxy hydrocarbons called kerogen.

Which shows the levels of organization within an ecosystem from largest to smallest?

the physical properties of 10 grams of iron are the same as the ___ properties of 20 grams of iron a) reactive b) physical c) chemical