In a science experiment showing the splitting of water into Oxygen and hydrogen, two inverted test tubes of water were placed over the site of the reaction. (see the pic) How can you tell which one was catching the oxygen and which one was catching the hydrogen?

A. The hydrogen is a positive ion and will be located close to the negative terminal of the battery.

B. The oxygen is a negative ion which will be located next to the negative terminal of the battery.

C. There are 2 hydrogen atoms for every oxygen atom. The hydrogen will take up more space and is pushing the water lower in the test tube.

D. The hydrogen, being a smaller atom, will take up less space than the oxygen. It will push the water down less.

The particle in a two-dimensional well is a useful model for the motion of electrons around the indole ring (3), the conjugated cycle found in the side chain of tryptophan. we may regard indole as a rectangle with sides of length 280 pm and 450 pm, with 10 electrons in the conjugated p system. as in case study 9.1, we assume that in the ground state of the molecule each quantized level is occupied by two electrons. (a) calculate the energy of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels. 9.27 electrons around the porphine ring (4), the conjugated macrocycle that forms the structural basis of the heme group and the chlorophylls. we may treat the group as a circular ring of radius 440 pm, with 20 electrons in the conjugated system moving along the perimeter of the ring. as in exercise 9.26, assume that in the ground state of the molecule quantized each level is occupied by two electrons. (a) calculate the energy and angular momentum of an electron in the highest occupied level. (b) calculate the frequency of radiation that can induce a transition between the highest occupied and lowest unoccupied levels.

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.

On mars a rock falls an unknown vertical distance from a resting position and lands in a crater. if it takes the rock 2.5 seconds to fall, how high is the cliff the rock fell from? mars' surface gravity is 3.8 m/s2.