PLEASEEEE HELP WITH THIS ID REALLY REALLY APPRECIATE IT

Calculate the adjusted retention times for both pentafluorobenzene and benzene if the elution time for unretained solute is 1.06

vovangra [49]

Answer:

Pentafluorobenzene: 11,92 min

Benzene: 12,14 min

Explanation:

Retention time of pentafluorobenzene is 12,98 min and 13,20 min of benzene.

The adjusted retention time is the time an analyte spends in the column not the stationary phase. As time of unretained solute is 1,06 min the adjusted retention time for an analyte is:

tr' = tr - 1,06min

For pentafluorobenzene:

tr' = 12,98min - 1,06min = 11,92 min

For benzene:

tr' = 13,20 - 1,06min = 12,14 min

I hope it helps!

3 0

2 years ago

A chemist must dilute of aqueous sodium carbonate solution until the concentration falls to . He'll do this by adding distilled

Mademuasel [1]

The question is incomplete, complete question is :

A chemist must dilute 73.9 mL of 400 mM aqueous sodium carbonate solution until the concentration falls to 125 mM . He'll do this by adding distilled water to the solution until it reaches a certain final volume. Calculate this final volume, in liters. Be sure your answer has the correct number of significant digits.

Answer:

The final volume of the solution will be 0.236 L.

Explanation:

Concentration of sodium carbonate solution before dilution = $M_1= 400 mM$

Volume of sodium carbonate solution before dilution = $V_1=73.9 mL$

Concentration of sodium carbonate solution after dilution = $M_2= 125 mM$

Volume of sodium carbonate solution after dilution = $V_2=?$

Dilution equation is given by:

$M_1V_1=M_2V_2$

$V_2=\frac{M_1V_1}{M_2}$

$V_2=\frac{400 mM\times 73.9 mL}{125 mM}= 236.48 mL\approx 236 mL$

1 mL = 0.001 L

236 mL = 0.236 L

The final volume of the solution will be 0.236 L.

3 0

3 years ago

Number 2 & 3 please !!<3

Goshia [24]

Answer:just for the ponits

Explanation:ima be a jenna

8 0

2 years ago

What happens to the pen?what could have caused the pen's motion? grade 8 asap

DedPeter [7]

Answer:

One is tension force that acts on the string and the other one is gravitational force that is acting on the pen and is therefore, the one that pulls the pen towards the ground. Therefore, the pen's motion is caused by the unbalanced force acting on the pen.

5 0

3 years ago

How will we know that a chemical reaction happened if we cant see atoms??

Mariana [72]

we can do soo by noticing any colour change, or by the formation of an insoluble precipitate or by the evolution of a gas.

6 0

2 years ago