Boron has two naturally occurring isotopes. Find the percent abundances of 10B and 11B given the isotopic mass of 10B = 10.0129 amu and the isotopic mass of 11B = 11.0093 amu.

Decomposition is the cycle at which bacteria breaks down any organic material into the soil

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf   

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.

Hello,#agreed with joseph002.i got my source also from  source: hope this