The first practical incandescent light bulb<span>. </span>Edison<span> and his team of researchers in </span>Edison's<span> laboratory in Menlo Park, N.J., tested more than 3,000 designs for </span>bulbs<span> between 1878 and 1880. In November 1879, </span>Edison<span> filed a patent for an electric </span>lamp<span> with a carbon filament.</span>
<span>Metals are usually good conductors because they have abundant free negative charges, or electrons.
</span>
The answer is Copper
Answer:
The pH of the buffer is 3.54.
Explanation:
To calculate the pH of acidic buffer, we use the equation given by Henderson Hasselbalch:
![pH=pK_a+\log(\frac{[salt]}{[acid]})](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%28%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7D%29)
![pH=pK_a+\log(\frac{[NaHCO_3]}{[H_2CO_3]})](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%28%5Cfrac%7B%5BNaHCO_3%5D%7D%7B%5BH_2CO_3%5D%7D%29)
We are given:
= negative logarithm of acid dissociation constant of carbonic acid
![pK_a=-\log[K_a]=-\[1.8\times 10^{-5}]=4.74](https://tex.z-dn.net/?f=pK_a%3D-%5Clog%5BK_a%5D%3D-%5C%5B1.8%5Ctimes%2010%5E%7B-5%7D%5D%3D4.74)
![[NaC_2H_3O_2]=0.059 M](https://tex.z-dn.net/?f=%5BNaC_2H_3O_2%5D%3D0.059%20M)
![[HC_2H_3O_2]=0.94 M](https://tex.z-dn.net/?f=%5BHC_2H_3O_2%5D%3D0.94%20M)
pH = ?
Putting values in above equation, we get:

The pH of the buffer is 3.54.
Answer:- 30 moles of oxygen are required if 12 moles of
are consumed.
Solution:- The given balanced equation is:

From this balanced equation, there is 2:5 mol ratio between
and
.
We are asked to calculate the moles of
required to react with 12 moles of
.
It's a mol to mol conversion and the set up for this would be as:

= 
So, 30 moles of oxygen are required to react with 12 moles of
.