A solution of glucose in water is labell | Class 12 Chemistry Chapter Solutions, Solutions NCERT Solutions

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter Solutions. This page offers a step-by-step solution to the specific question from Exercise 2, Question 5: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 5:

A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? If the density of solution is 1.2 g mL-1, then what shall be the molarity of the solution?

Answer:

10% w/w solution of glucose in water means that 10 g of glucose in present in 100 g of the solution i.e., 10 g of glucose is present in (100 - 10) g = 90 g of water.

Molar mass of glucose (C6H12O6) = 6 × 12 + 12 × 1 + 6 × 16 = 180 g mol - 1

Then, number of moles of glucose = 10 / 180 mol

= 0.056 mol

∴ Molality of solution = 0.056 mol / 0.09kg  = 0.62 m

Number of moles of water = 90g / 18g mol-1 = 5 mol

Mole fraction of glucose  (xg) = 0.056 / ( 0.056+5) = 0.011

And, mole fraction of water xw = 1 - xg

= 1 - 0.011 = 0.989

If the density of the solution is 1.2 g mL - 1, then the volume of the 100 g solution can be given as:

= 100g / 1.2g mL-1

= 83.33 mL

=83.33 x 10-3 L

∴ Molarity of the solution = 0.056 mol / 83.33 x 10-3 L

= 0.67 M


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Solutions.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

Latest Blog Posts

Stay updated with our latest educational content and study tips

Smart Questions to Ask in a Parent-Teacher Meeting | PTM Made Easy

Parent-Teacher Meetings (PTMs) are more than quick updates on marks — they’re a chance to build a real partnership between home and school. A good Parent-Teacher Meeting conversation helps parents see beyond grades. It opens up insights about a child’s strengths, struggles, emotions and even hidden talents. When parents participate actively, they don’t just track […]

Read More

The Secret to Smarter Learning — Building Strong Critical Thinking Skills

In today’s world of endless information , knowing how to think is more important than knowing what to think . From school projects to real – life decisions , critical thinking helps students question ideas , analyze facts and form logical conclusions . But what exactly does critical thinking mean ? Simply put , it’s […]

Read More

Study Smarter, Not Harder: Build Productive Habits That Stick

Every student dreams of better grades , stronger focus and more study time – but the real challenge isn’t starting, it’s staying consistent . Building productive study habits is not about studying all day , it’s about studying smart . In today’s fast – paced digital world, distractions are everywhere – from endless phone notifications […]

Read More

The Hidden Risks of Online Gaming for Children — Is your child safe while gaming online?

Online gaming has rapidly become one of the most popular pastimes among children. Whether it’s multiplayer mobile games , PC adventures or console challenges , kids are spending more time than ever in the virtual world . On the surface, gaming seems entertaining and even educational – improving hand- eye coordination , teamwork and problem […]

Read More

Comments

  • Devanshi patkr
  • Jul 31, 2020

Thx for helping me 😊


  • Sonali
  • Jul 07, 2019

1000/90 can be written as 0.09


  • Sonali
  • Jul 07, 2019

1000/90 can be written as 0.09


  • Nazish
  • Jun 08, 2019

Why 19 was divided by 18.instead of 180


  • Amarjeet
  • May 24, 2019

From where 0.9 is there


  • Viku
  • May 20, 2019

0.9 kha s aaya h


  • Monika
  • Mar 30, 2019

When we get 0.01


  • Abab
  • Mar 17, 2019

Hey


  • Aksh
  • Jan 06, 2019

What if density is not given


  • Surendra singh kohli
  • Apr 25, 2018

Very interesting question


Add Comment

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 5: A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction ....