Question

100 POINTS PLEASE HELP (PHOTOS INCLUDED)

Answer 1

Step-by-step explanation:

3.

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

2.

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

Answer 2

Moles of solute be x

#1

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

`\\ \rm\Rrightarrow Molarity=(Moles\:of\:solute)/(Volume\:of\'solution)`

`\\ \rm\Rrightarrow 0.7=(x)/(0.1)`

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

`\\ \rm\Rrightarrow x=0.07mol`

#2

Same like before

• Volume of solution=5.5L
• Molarity=0.4M

`\\ \rm\Rrightarrow (x)/(5.5)=0.4`

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

`\\ \rm\Rrightarrow x=2.20mol`