Chemistry Worksheet Class 11 on Chapter 1 Some Basic Concepts of Chemistry with Answers - Set 5

The study of the composition, structure, and properties of matter, as well as the changes that matter undergoes under various conditions and the laws that govern these changes, is referred to as chemistry.

Chemistry can be useful in a variety of situations in life. Here are some of Chemistry’s most important applications:

  • Chemical reactions take place in the food we eat, the cosmetics we use, and the medications we take.
  • It can help you make decisions on a variety of topics, such as when to water plants based on the season, what temperature to bake a cake at, which medicine to use for acidity, how to apply a specific SPF sunscreen, and so on.
  • It helps you determine which element your body needs the most. For example, some people may require more Vitamin D than others.
  • It is also used to improve health, create new elements, supply metals and nuclear energy, manufacture industrial equipment, and is used in wars and building materials.

Download PDF of Class 11 Chemistry Chapter 1 Some Basic Concepts of Chemistry – Set 5
Download PDF

Chemistry Worksheet Class 11 on Chapter 1 Some Basic Concepts of Chemistry with Answers - Set 5
Chemistry Worksheet Class 11 on Chapter 1 Some Basic Concepts of Chemistry with Answers - Set 5
Chemistry Worksheet Class 11 on Chapter 1 Some Basic Concepts of Chemistry with Answers - Set 5

CBSE Class 11 Chemistry Worksheet Chapter 1 Some Basic Concepts of Chemistry – Set 5

Q1. What is the molality of pure water?

a.) 1 m

b.) 18 m

c.) 55.5 m

d.) None of the above

Q2. 4L of water is added to 2L of 6 M HCl. The molarity of the final solution is:

a.) 4M

b.) 2 M

c.) 1 M

d.) 0.5 M

Q3. A sample of water contains x% of D2O. Its molecular weight is 19. The value of x is ____.

a.) 25

b.) 50

c.) 33.33

d.) 75

Q4. Two different oxides of a metal contain 20% and 27% oxygen by weight. This is in accordance with the ____.

a.) Law of multiple proportions

b.) Law of conservation of mass

c.) Law of conservation of energy

d.) Law of constant proportions

Q5. The number of significant figures in 0.0101 is ____.

a.) 2

b.) 3

c.) 4

d.) 5

Q6. Which postulate of Dalton’s atomic theory was modified after the discovery of isotopes?

Q7. State Gay Lussac’s law.

Q8. Give the SI units for

i.) Volume

ii.) Speed

iii.) Force

Q9. Which of the following has maximum mass?

a.) 2.6 grams atoms of sulphur

b.) 2.6 grams molecules of sucrose (C12H22O11)

c.) 2.6 grams of iodine

Q10.

a.) Express the following numbers in exponential notations to three significant figures:

i.) 900035

ii.) 0.000002136

iii.) 406721

iv.) 0.000001

b.) Round up the following up to three significant figures:

i.) 34.216

ii.) 10.4107

iii.) 0.04597

iv.) 2808

Q11. Why is molality preferred over molarity in expressing the concentration of a solution?

Q12. If 6.3 g of NaHCO3 are added to 15.0 g of CH3COOH solution, the residue is found to weigh 18.0 g. What is the mass of CO2 released in the reaction?

Q13. Calculate the number of molecules of carbon dioxide present in 300 mL of gas at 273 K and 2.5 atm pressure.

Q14. P4O6 and P4O10 are formed by burning P4 with O2 as

P4 + 3O2 → P4O6

P4 + 5O2 → P4O10

What are the masses of P4O6 and P4O10 that will be produced by the combustion of 2.0 g of P4 in 2.0 g of oxygen, leaving no P4 and O2?

Q15. Calculate:

a.) The actual volume of one molecule of water.

b.) The radius of the water molecule assuming to be spherical (density of water = 1 g mL–1}.

Q16. Differentiate between compounds and mixtures.

Q17. a.) Calculate the number of molecules and atoms present in 5.60 L of ozone (O3) at N.T.P.

b.) How many molecules of CO2 are present in one litre of air containing 0.03% by volume of CO2 at STP?

Q18. Calculate the percentage composition of the following compounds:

i.) Urea CO(NH2)2

ii.) Copper sulphate CuSO4.5H2O

Q19. A solution of glucose in water is labelled as 10% (w/w). The density of the solution is 1.0 g mL–1. Calculate

i.) Molality

ii.) Molarity

iii.) Mole fraction of each component in the solution

Q20. Calculate the empirical formula and molecular formula of a compound having percentage composition as:

Iron = 20%, sulphur = 11.5%, oxygen = 23.1% and water molecule = 45.4%

The molecular mass of the compound is 278 g. Also, name the compound.

Download PDF to access answers of the Chemistry Worksheet for Class 11 Chemistry Chapter 1 Some Basic Concepts of Chemistry Set – 5
Download PDF

Read Also:

CHEMISTRY Related Links
Titration Definition Eutrophication Definition
Mass Spectrometry Principle Thermal Conductivity
Dalton'S Atomic Theory Difference Between Evaporation And Vaporization
Sodium Chloride Uses Modern Periodic Law
Reverse Osmosis Definition Effects Of Radiation