As a couple of people have pointed out, human hearing ranges from 10 Hz to 10,000 Hz, but as people get older and as they damage their hearing by listening to very loud music, firing guns without ear protection, working in very noisy environments or having other physical damage, that upper end drops off. At 64 yrs old, with a long history of a target shooter before we thought about ear protection, and after many years as a rock and roll disk jockey.<span>
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3Na2O(at) + 2Al(NO3)3(aq) —> 6NaNO3(aq) + Al2O3(s)
This is a double replacement reaction and NaNO3 is aqueous because Na is an alkali metal, plus nitrate is in the solution. Both of these are soluble. Al2O3 is not soluble because it does not contain any element that is soluble and is hence the precipitate.
Hope this helped!
There is no direct way to convert from the mass of one substance to the mass of another. To convert from one mass (substance A) to another mass (substance B), you must convert the mass of A first to moles, then use the mole-to-mole conversion factor (B/A), then convert the mole amount of B back to grams of B.
Answer:
D.) reducing agent
Explanation:
Oxidized chemicals gain electrons. In order to gain these electrons, another chemical must lose electrons. So, the chemical (which will be oxidized) acts as a reducing agent, causing the other chemical to be reduced and lose electrons.
Answer:
1.07×10²¹ molecules are needed to sound the alarm
Explanation:
Let's convert the mass of CO to moles, to determine the amount of molecules.
0.05 g . 1 mol / 28 g = 1.78×10⁻³ moles
Now we can determine the number of molecules with the NA
1 mol has 6.02×10²³ molecules
1.78×10⁻³ moles may have (1.78×10⁻³ . 6.02×10²³) / 1 = 1.07×10²¹ molecules
