The graph below shows the amount of different compounds that make up an animal cell what percentage of the total cell weight is made up of lipids

Enough of a monoprotic weak acid is dissolved in water to produce a 0.0172 m solution. if the ph of the resulting solution is 2.39 at 20 °c, determine the pka for the acid.

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

Athe top of a hill, an athlete on a skateboard has x joules of mechanical energy. how much mechanical energy will she have at the bottom of the hill? ignore the effects of friction.