The movement of carbon from CO2 in the atmosphere to HCO3- (a byproduct of chemical weathering) on rocks to CaCO3 in coral skeletons and, finally, to CaCO3 in limestone are all steps in the cycle.

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?

Identify one disadvantage to each of the following models of electron configuration: -dot structures -arrow and line diagrams -written electron configurations type in your answer below. (answer) -dot structures do not show the distribution of electrons in orbitals and take up a lot of space. -arrow and line diagrams take up a lot of space and make it difficult to count electrons. -written configurations make it easy to lose count of electrons and do not show the distribution of electrons in orbitals.