<u>Answer:</u> The amount of sample left after 20 years is 288.522 g and after 50 years is 144.26 g
<u>Explanation:</u>
We are given a function that calculates the amount of sample remaining after 't' years, which is:
![A_t(t)=458\times (\frac{1}{2})^{\frac{t}{30}](https://tex.z-dn.net/?f=A_t%28t%29%3D458%5Ctimes%20%28%5Cfrac%7B1%7D%7B2%7D%29%5E%7B%5Cfrac%7Bt%7D%7B30%7D)
Putting values in above equation:
![A_t(t)=458\times (\frac{1}{2})^{\frac{20}{30}](https://tex.z-dn.net/?f=A_t%28t%29%3D458%5Ctimes%20%28%5Cfrac%7B1%7D%7B2%7D%29%5E%7B%5Cfrac%7B20%7D%7B30%7D)
![A_t(t)=288.522g](https://tex.z-dn.net/?f=A_t%28t%29%3D288.522g)
Hence, the amount of sample left after 20 years is 288.522 g
Putting values in above equation:
![A_t(t)=458\times (\frac{1}{2})^{\frac{50}{30}](https://tex.z-dn.net/?f=A_t%28t%29%3D458%5Ctimes%20%28%5Cfrac%7B1%7D%7B2%7D%29%5E%7B%5Cfrac%7B50%7D%7B30%7D)
![A_t(t)=144.26g](https://tex.z-dn.net/?f=A_t%28t%29%3D144.26g)
Hence, the amount of sample left after 50 years is 144.26 g
M ( HCl ) = ?
V ( HCl ) = 25.5 mL in liters : 25.5 / 1000 => 0.0255 L
M ( NaOH ) = 0.113 M
V ( NaOH ) = 51.2 mL / 1000 => 0.0512 L
number of moles NaOH:
n = M x V
n = 0.113 x <span> 0.0512 => 0.0057856 moles of NaOH
mole ratio:
</span><span>HCl + NaOH = NaCl + H2O
</span><span>
1 mole HCl -------------- 1 mole NaOH
( moles HCl ) ----------- </span><span> 0.0057856 moles NaOH
</span>
(moles HCl ) = <span> 0.0057856 x 1 / 1
</span>
= <span> 0.0057856 moles of HCl
</span>
M ( HCl ) = n / V
M = 0.0057856 / <span>0.0255
</span>
= 0.227 M
Answer A
hope this helps!
1. A soluble salt can be prepared by reacting an acid with a suitable insoluble reactant including:
a metal
a metal oxide
a carbonate
3. I don’t know this one
4. A term base or glossary is a database containing single words or expressions related to a specific subject.
5. Strong acid is an acid that ionizes completely in aqueous solution. It always loses a proton (H+) when dissolved in water. Weak acid is an acid that ionizes partially in a solution. ... Because the rate of reaction depends upon the degree of dissociation αand strong acids have higher degrees of dissociation.
im not sure of the rest
The answer is D: Products combine to produce new reactants... Hope this helps! :)
Explanation:
The answer to questions are
A) 4
B) 3
C) 5
D) 3
E) 3