Simple!
Atomic number= number of protons AND number of electrons (in an atom)
Mass number= number of neutrons
Answer:
Electron affinity increases upward for the groups and from left to right across periods of a periodic table because the electrons added to energy levels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons.
Methane (CH4) = 1 carbon atom, 4 hydrogen
Sulphuric Acid (H2SO4) = 2 hydrogen atoms, 1 sulfur and 4 oxygen.
You need to monitor the solution to see when the crystals start gathering at the bottom of the solution. You can slowly add alum until it stops dissolving. The point just before it starts its sedimentation at the bottom is the point when the solution is saturated.
