First, let's write the givens in the form of a chemical equation:
3A + B ...................> 4X + 2Y
Now we find that this equation implies the following:
For every 4X and 2Y formation, 3A and 1B must disappear (react).
Comparing this implication to the above choices, we find that the right answer is: <span>The rate of formation of X is four times the rate of disappearance of B.</span>
The answer is <span>non-biodegradable and subject to bioaccumulation and/or bioamplification.
DDT (dichlorodiphenyltrichloroethane) is persistent, non-degradable insecticide and organic pollutant readily accumulated to soils and consequently affects organisms.
DDE (</span><span>dichlorodiphenyldichloroethylene) is non-degradable pesticide toxic to birds at the first place.
PCBs (polychlorinated biphenyls) are non-degradable organic compounds very toxic to the environment.
PBDEs (polybrominated diphenyl ethers) are non-degradable compounds very toxic to environment, even able to affect brains of animals in the development period.</span>
so basically
some fuels have an impurity in them which is sulfur.
When the fuel undergoes combustion, the sulfur reacts with oxygen in the air to form sulfur dioxide.
the sulfur dioxide reacts with water vapour in the air to form sulfurous acid, which is a type of acid rain.
Also
the high pressures inside a car engine may cause nitrogen and oxygen in the air to react and form oxides of nitrogen. the most common compounds formed inside car engines are NO (nitrogen oxide) and NO2 (nitrogen dioxide)
The balanced half reactions are
4 Fe2+ ====> 4 Fe3+ + 4 e-
<span>MnO42- + 8 H+ + 4 e- ===> Mn2+ + 4 H2O
The net ionic equation is
4 Fe2+ + </span>MnO42- + 8 H+ ===> 4 Fe3+ + Mn2+ + 4 H2O<span />
The answer is b) the highest occupied orbital is a “d”orbital.
Transition metals are metals where the highest energy electrons partially fill the d subshells. There are some elements with complete d subshells but on forming cations they have incomplete d subshells.
These transition metals have some properties that are different from the other metals .