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3 years ago

100 POINTS PLEASE HELP (PHOTOS INCLUDED)

Chemistry

2 answers:

Anton [14]3 years ago

7 0

Moles of solute be x

Volume of solution=100mL=0.1mL
Molarity=0.7M

$\\ \rm\Rrightarrow Molarity=\dfrac{Moles\:of\:solute}{Volume\:of\'solution}$

$\\ \rm\Rrightarrow 0.7=\dfrac{x}{0.1}$

$\\ \rm\Rrightarrow x=0.1(0.7)$

$\\ \rm\Rrightarrow x=0.07mol$

Same like before

Volume of solution=5.5L
Molarity=0.4M

$\\ \rm\Rrightarrow \dfrac{x}{5.5}=0.4$

$\\ \rm\Rrightarrow x=5.5(0.4)$

$\\ \rm\Rrightarrow x=2.20mol$

pshichka [43]3 years ago

6 0

Answer:

Explanation:

Knowns: 100mL of solution; concentration of 0.7M

Unknown: number of moles

Equation: number of moles = volume * concentration

Plug and Chug: number of moles = 100/1000 * 0.7 = 0.07 mole

Final Answer: 0.07mole

Knowns: 5.50L of solution; concentration of 0.400M

Unknown: number of moles

Equation: number of moles = volume * concentration

Plug and Chug: number of moles = 5.5 * 0.4 = 2.20 mole

Final Answer: 2.20 mole

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