A negative ion or anion is an electrically charged atom or group of atoms that are formed by gaining one or more electrons. Whereas a positive ion or cation is an electrically charged atom or group of atoms that are formed by losing one or more electrons. The losing and gaining all occurs on the outermost shell.
<em>Which of the following statements is TRUE?</em>
<em>A. State functions do not depend on the path taken to arrive at a particular state.</em> TRUE. State functions like enthalpy (ΔH) and internal energy (ΔE) do not depend on the trajectory, but on the initial and final state.
<em>B. Energy is neither created nor destroyed, excluding nuclear reactions.</em> TRUE. Only in nuclear reactions can energy (E) can be transformed in matter (m) and vice-versa according to Einstein equation: E = m . c² (c is the speed of light).
<em>C. ΔHrx can be determined using constant pressure calorimetry.</em> TRUE. The enthalpy of reaction is the heat involved at constant pressure.
<em>D. ΔErx can be determined using constant volume calorimetry.</em> TRUE. The internal energy of reaction is the heat involved at constant volume.