Greater amplitude waves have more energy and greater intensity, so they sound louder. ... The same amount of energy is spread over a greater area, so the intensity and loudness of the sound is less. This explains why even loud sounds fade away as you move farther from the source.
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Answer:
12.8 g of 
must be withdrawn from tank
Explanation:
Let's assume gas inside tank behaves ideally.
According to ideal gas equation- 
where P is pressure of , V is volume of , n is number of moles of , R is gas constant and T is temperature in kelvin scale.
We can also write, 
Here V, T and R are constants.
So, 
ratio will also be constant before and after removal of from tank
Hence, 
Here, 
and 
So, 
So, moles of must be withdrawn = (0.66 - 0.26) mol = 0.40 mol
Molar mass of = 32 g/mol
So, mass of must be withdrawn = 
Answer:
Redox type
Explanation:
The reaction is:
2Cr + 3Fe(NO₃)₂ → 2Fe + 2Cr(NO₃)₃
2 moles of chromium can react to 3 moles of iron (II) nitrate in order to produce 2 moles of iron and 2 moles of chromium nitrate.
If we see oxidation state, we see that chromium changes from 0 to +3
Iron changed the oxidation state from +2 to 0
Remember that elements at ground state has 0, as oxidation state.
Iron is being reduced while chromium is oxidized. Then, the half reactions are:
Fe²⁺ + 2e⁻ ⇄ Fe (Reduction)
Cr ⇄ Cr³⁺ + 3e⁻ (Oxidation)
When an element is being reduced, while another is being oxidized, we are in prescence of a redox reaction.
