Which of the following combinations will result in a reaction that is never spontaneous?
1) positive enthalpy change and positive entropy change
2) positive enthalpy change and negative entropy change
3) negative enthalpy change and positive entropy change
4) negative enthalpy change and negative entropy change

What is the mass defect of a mole of nuclei with 1.8 x 10^15 j/mol binding energy?

This drawing shows a human body system. what is the primary function of this body system?

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.