The shielding of electrons gives rise to an effective nuclear charge, ZeffZeff, which explains why boron is larger than oxygen. Estimate the approximate ZeffZeff felt by a valence electron of boron and oxygen, respectively

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.

answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck

its first and third is your answer i did the qustion the fourth isnt right