Answer:
<h3>The answer is 8.29 %</h3>
Explanation:
The percentage error of a certain measurement can be found by using the formula

From the question
actual density = 19.30g/L
error = 20.9 - 19.3 = 1.6
We have

We have the final answer as
<h3>8.29 %</h3>
Hope this helps you
 
        
             
        
        
        
Answer:
Scientists believe the batteries (if that is their correct function) were used to electroplate items such as putting a layer of one metal (gold) onto the surface of another (silver), a method still practiced in Iraq today.
Explanation:
 
        
             
        
        
        
The concentration of a substance is the quantity of solute present in a given quantity of solution.
 
        
             
        
        
        
There is one missing point in the question.
The formula to find an increase in boiling Temperature is :
ΔT = kb x M
ΔT = is the increase in boiling Temperature
Kb = Boiling point constant of the Solvent
M = Molarity
You did not provide the Kb. If you have it, you just have to insert it to the formula to find the ΔT.
And assuming that the other solution is water, you just have to add it up with 100 Celcius