Answer:
electrons fill lower energy levels first before occupying higher energy levels.
Explanation:
The Aufbau's principle describes that electrons fill lower energy levels first before occupying higher energy levels.
In writing the electronic configuration of atoms, the Aufbau's principle is one of the most important principles to consider.
It states that "sublevels with with lower energies are filled up before those with higher energies".
Sublevels do not fill up in numerical order.
Answer:
Anions electronic configuration is given by adding electrons.
Answer : The final pressure of the basketball is, 0.990 atm
Explanation :
Gay-Lussac's Law : It is defined as the pressure of the gas is directly proportional to the temperature of the gas at constant volume and number of moles.
or,
where,
= initial pressure = 1.10 atm
= final pressure = ?
= initial temperature = 
= initial temperature = 
Now put all the given values in the above equation, we get:
Thus, the final pressure of the basketball is, 0.990 atm
Answer: The reaction is exothermic. The value of q is -542 kJ.
Explanation:
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and for the reaction comes out to be positive.
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.
Thus 
evolves heat , it is exothermic in nature. The value of q is -542kJ.
On the other hand ammonia is a very dangerous chemical which has a pungent smell and effect the eyes of the user. Thus it kept always in the fume exhaust hood for storing and dispensing function.
The pH of ammonia buffer contains ammonium hydroxide (NH₄OH) and a salt of ammonia with a strong acid like (HCl) which produces, ammonium chloride (NH₄Cl) mixture. The evaporation rate of ammonia is so high at room temperature thus on opening of the buffer solution the ammonia get evaporated very fast and the concentration of ammonia decreases which affect the pH of the buffer solution.
Thus the reason to put ammonia buffer in fume hood is explained.
