The correct answer is letter C
Answer:
Transition Element
Explanation:
Transition elements are defined as those elements which can form at least one stable ion and has partially filled d-orbitals. They are also characterized by forming complex compounds and having different oxidation states for a single metal element.
Transition metals are present between the metals and the non metals in the periodic table occupying groups from 3 to 12. There general electronic configuration is as follow,
(n-1)d
¹⁻¹⁰ns
¹⁻²
The general configuration shows that for a given metal, the d sublevel will be in lower energy level as compared to corresponding s sublevel. For example,
Scandium is present in fourth period hence, its s sublevel is present in 4rth energy level so its d sublevel will be present in 3rd energy level respectively.
Hence, we can conclude that for transition metals the electron are present in highest occupied s sublevel and a nearby d sublevel
.
A. Reactants, products
In a chemical reaction, reactants interact to form products
Answer:
Hydrogen Chloride Gas is heavier than air and sinks to the ground after being released. Firefighters closer to the ground will be subjected to significantly greater concentrations of hydrogen chloride gas than the firefighters walking on top of railcars.
Explanation:
The molar mass of air is 28.97 g/mol. Air is approximately 78% N2, which has a molar mass of 28.014 g/mol and 21% oxygen, which has a molar mass of 32 g/mol; the remaining constituents of air include CO2 and other trace amounts of gases.
The molar mass of HCl is 36.458 g/mol.
Because HCl is heavier than air, it sinks toward the ground, displacing the lighter air.
The height of railway cars is reported to vary between 13.5 ft to 15.5 ft. So firefighters on tank cars are generally above the HCl gas (although localized atmospheric conditions could cause the HCl to move higher up in the air column).