Complete the Lewis structures for pyrazine (C5H4N2) showing the two most common resonance forms. Draw the Lewis structures with the formal charges minimized.

What is a metal replacement reaction

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?

If the concentration of phosphate in the cytosol is 2.0 mm and the concentration of phosphate in the surrounding fluid is 0.1 mm, how could the cell increase the concentration of phosphate in the cytosol? a) passive transportb) diffusionc) active transportd) osmosise) facilitated diffusion