The element lithium has two common isotopes: Li–6 and Li–7 If the average atomic mass of lithium is 6.94004 u, determine its percent isotopic abundances. Step by step and explain.

Freezing and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

The kw for water at 0 °c is 0.12× 10–14 m2. calculate the ph of a neutral aqueous solution at 0 °c.

Use the de broglie's wave equation to find the wavelength of an electron moving at 7.3 × 106 m/s. show your work. note: h = plank's constant (6.62607 x 10-34 j s)