What two particles account for almost all of the mass of an atom?

Consider the following multistep reaction: a b→ab(slow) a ab→a2b(fast)−−−−−−−−−−−−−−−−− 2a b→a2b(overall) based on this mechanism, determine the rate law for the overall reaction. express your answer in standard masteringchemistry format. for example, if the rate law is k[a]3[b]2 type k*[a]^3*[b]^2

The table lists the lattice energies of some compounds.compoundlattice energy (kj/mol)lif            –1,036licl            –853naf            –923kf            –821nacl            –786which statement about crystal lattice energy is  best  supported by the information in the table? the lattice energy increases as cations get smaller, as shown by lif and kf.the lattice energy increases as the cations get larger, as shown by lif and licl.the lattice energy decreases as cations get smaller, as shown by nacl and naf.the lattice energy decreases as the cations get smaller, as shown by naf and kf.

Acompound has the molecular formula c3h8. which class of organic compounds does it belong to?