Answer:
31.43 ml of sulfuric acid is needed to react with 23.1 g of barium peroxide.
Explanation:
For the reaction:
BaO₂(s) + H₂SO₄(aq) ⇒ BaSO₄(s) + H₂O₂(aq)
We need 1 mole of BaO₂ to react with 1 mole of H₂SO₄ and then forming 1 mole of BaSO₄ and 1 mole of H₂O₂.
We know that 4.5 M solution of H₂SO₄ means 4.5 moles of H₂SO₄ in 1000 ml of solution.
Then,
23.1 g BaO₂ × ×
×
= 31.43 ml H₂SO₄
(B) F
(C) O
(D) Ca
(E) Na
Object A at 40 degrees C and object B at 80 degrees C are placed in contact with each other. The heat flow will flow from the Object B to the object A because of temperature difference. To attain equilibrium, the heat flow must flow form a higher temperature to a lower temperature.
Answer:
The de-exitation of electron to its lower energy level cause the emission spectrum of an element.
Explanation:
The electron is jumped into higher level and back into lower level by absorbing and releasing the energy.
The process is called excitation and de-excitation.
Excitation:
When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits. For example if electron jumped from K to L it must absorbed the energy which is equal the energy difference of these two level. The excited electron thus move back to lower energy level which is K by releasing the energy because electron can not stay longer in higher energy level and comes to ground state.
De-excitation:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. This energy is exactly equal to the energy difference between the orbits. These radiations gives the emission spectrum of that element. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum.
The atomic emission spectrum of an element is produced by the energy released when an electron transitions from a higher to a lower energy level. This energy is emitted as light, creating a unique spectrum that can be used to identify the element.
The atomic emission spectrum of an element is caused by the energy released when an electron in an atom moves from a higher energy level to a lower energy level. When an atom absorbs energy, it moves its orbiting electrons to a higher energy level. However, these electrons cannot maintain this high energy state for long, forcing them to transition back to their original or lower energy level. The energy they release during this transition is emitted in the form of light, creating a unique emission spectrum.
For example, hydrogen has a characteristic series of emission lines in its spectrum (Balmer series) because the electrons in a hydrogen atom can occupy specific energy levels. When these electrons drop from a higher energy level to a lower one, they emit light of specific wavelengths, creating the unique atomic emission spectrum of hydrogen.
#SPJ6