Given that 1 mole contains 6.02x10^23 molecules, 3.0x10^23 is just around half a mole. Then we check the number of moles for each choice:
A. This is approximately half a mole, since the molar mass of Br2 is 159.8 g/mol.
B. He has a molar mass around 4 g/mol, so this is 1 mole.
C. H2 has a molar mass of 2.02 g/mol, so this is 2 moles.
D. Li has a molar mass of around 6.97 g/mol, so this is around 2 moles.
Therefore the only choice that fits is A. 80 g of Br2.
The high surface tension helps the paper clip - with much higher density - float on the water. The property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of its molecules.
Basically it means that there is a sort of skin on the surface of water where the water molecules hold on tight together. If the conditions are right, they can hold tight enough to support your paper clip. The paperclip is not truly floating, it is being held up by the surface tension.
The flow of stimuli information in the body is from the receptors to sensory neuron (afferent neurons) to the interneurons then to the central nervous system (brain and spinal cord) then is carried of by the motor neurons (efferent neurons) to the mucles involve.
Sensation to transduction to perception. Sensation is the ambiguous information which is received by the receptors or sensory organ henceforth, transduction occurs in the nerve cell protruding to the brain and is now called perception as the vague stimuli is interpreted and processed to be understood then is responded with the proper and apt response or reaction.
