Question

18grams of glucose dissolved in 180 g of water. find mole fraction o glucose and molarity of the situation

Answer 1

Answer:

Explanation:mass of glucose=18g

Molecular mass of glucose=180u

Moles of glucose in solution=18/180=0.1mol

Mass of water=180g

Molecular mass of water=18g

Moles of water=180/18=10mol

Mole fraction of glucose=0.1/10+0.1=0.0099

Total mass of solution=180+18=198g

Moles of solute=0.0099mol

Molarity=0.0099/198*1000=0.05M

Answer 2

Hi,

Here is your answer

Given:

Mass of glucose=18g

Mass of water=180g

To Find:

a)Mole fraction of glucose

b)Molarity of solution

Solution:

a)

Number of moles of glucose=Given mass/Molar mass

Molar mass of glucose=12×6+12+16×6=180

Hence

Number of moles of glucose=18/180=0.1 moles

Molar mass of water=2+16=18

Number of moles of water=180/18=10moles

Mole fraction of glucose=Number of moles of glucose/number of moles of solution

Moles fraction of glucose=0.1/0.1+10=0.0099

b)

Molarity=number of moles of glucose×1000/180

Molarity=0.1×1000/180              

Molarity=0.55M

Notes:

1. The equation for finding molarity

Molarity=number of moles of solute/Volume of solution in litre

2. The unit of molarity is M or mol/L

Hope this helps you.