The answer is : 17.5 liters drained and replaced by 17.5 liters of 100% solution.  
x = amount drained and replaced
(70-x) = remaining amount of 20% solution
<span>.20(70-x) + 1.00(x) = .40(70)
14 - .2x + 1x = 28
1x - .2x = 28 - 14
</span><span>.8x = 14
</span><span>x = 14/.8
x= 17,5 ( 17.5 liters drained and replaced by 17.5 liters of 100% solution)
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Answer:
I think It's C
Explanation:
due to higher waves can get easy transfers and receive those signals for most things, such as radios, TVs, phone signals etc etc
 
        
             
        
        
        
Answer:
Neon
Explanation:
Step 1: Given and required data
- Density of the gas (ρ): 1.57 g/L
- Ideal gas constant (R): 0.08206 atm.L/mol.K
Step 2: Convert T to Kelvin
We will use the following expression.
K = °C + 273.15 = 40.0 + 273.15 = 313.2 K
Step 3: Calculate the molar mass of the gas (M)
For an ideal gas, we will use the following expression.
ρ = P × M/R × T
M = ρ × R × T/P
M = 1.57 g/L × 0.08206 atm.L/mol.K × 313.2 K/2.00 atm
M = 20.17 g/mol
The gas with a molar mass of 20.17 g/mol is Neon.
 
        
             
        
        
        
Answer:
Pb(NO3)2(aq) + 2NaCl(aq) -> 2NaNO3(aq)+PbCl2(s)
Explanation:
Pb(NO3)2(aq)+NaCl(aq) -> NaNO3(aq)+PbCl2(s)
This is how it starts out.
Left: 
Right
So the place to start with this equation is to bring the Cls up to 2
Pb(NO3)2(aq)+2NaCl(aq) -> NaNO3(aq)+PbCl2(s)
But the Nas are now out of kilter.
Pb(NO3)2(aq)+ 2NaCl(aq) -> NaNO3(aq)+PbCl2(s)
Now the right has a problem. There's only 1 Na
Pb(NO3)2(aq) + 2 NaCl(aq) -> 2NaNO3(aq)+PbCl2(s)
Check it out. It looks like we are done.
 
        
             
        
        
        
Answer:
The yeast respired aerobically
Explanation:
The expectation here was that the yeast was going to put the sugar in the grape juice through fermentation, which is an anaerobic process that results in alcohol as one of the products. However since no alcohol was found in this particular example, it is fair to assume that maybe there was oxygen in teh muxture and therefore the yeast respired aerobically, producing water and carbon dioxide as products.