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A standard solution contained 0.842 g/L of solute. A student put 0.2mL of standard and 0.8mL water into a test tube. What is the new concentration in mg/mL? answer with 2 to 4 decimal places rounding correctly, without units.

Respuesta :

Dejanras
Answer is: new concentration is 0,168 mg/mL.
d(solution) = 0,842 g/L.
V(solution) = 0,2 mL = 0,0002 L.
V(water) = 0,8 mL.
Vā‚(solution) = V(solution) + V(water).
Vā‚(solution) = 0,8 mL + 0,2 mL = 1 mL.
m(solution) = 0,0002 L Ā· 0,842 g/L Ā· 1000.
m(solution) = 0,168 mg.
dā‚(solution) = m(solution) / Vā‚(solution).
dā‚(solution) = 0,168 mg/mL.