What is in the cloud of negatively charged particles that surrounds an atom?

a. proteins
b. neutrons
c. electrons
d. protons

Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

If a molecule with a molecular formula of c13h18 is treated with an excess of h2 in the presence of finally divided pt metal under conditions required for maximum hydrogenation of the molecule to give a molecule with a formula c13h24, how many rings are in the molecule?

Which statement about hf is true? it is zero for any compound in its standard state. it is positive when the bonds of the product store more energy than those of the reactants. it is negative when a compound forms from elements in their standard states. it is zero for any element that is in the liquid state.