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Explore Class 10 Compulsory Science and Technology past and model questions by chapter, year, marks and question type.
322 questions found
Study the part of the periodic table given below and answer the following questions.
Groups | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
Period 2 | X | A | M | |||||
Period 3 | Y | B | J |
Study the given diagram and answer the following questions.
Check the correctness of the equation by using unit-wise analysis.
a.What is meant by homologous series of hydrocarbon?
Ans: A homologous series is described as a family of related organic compounds sharing comparable molecular structures and consistent chemical traits, where neighboring members vary progressively by a increment.
b. An example of a homologous series of hydrocarbons is given in the table alongside. | Compound | Homologous Series | | :--- | :--- | | A | | | B | | | C | |
(i) Write the IUPAC name of the compound 'B'.
Ans: The systematic IUPAC identifier corresponding to compound 'B' is propane.
(ii) Write the structural formula of the compound formed when one hydrogen atom of compound 'A' is disabled by '-OH'.
Ans: Exchanging a single hydrogen atom on compound 'A' with a hydroxyl group produces ethyl alcohol.
H ──C───C───H +OH ► H ──C───C───OH │ │ │ │ H H H H (Ethane) (Ethyl alcohol)
(iii) Write the general molecular formula of the compound formed when one hydrogen atom from each of two middle carbon atoms is removed from the compound 'C'.
Ans: Eliminating one hydrogen atom from both central carbon atoms of compound 'C' yields butene, which is represented by the chemical formula .
Draw a well labelled diagram of the laboratory preparation of the gas formed by the reaction between calcium carbonate and dilute hydrochloric acid.
A. a microwave oven has a ratio of secondary to primary windings equal to . IF the microwave oven is connected to a source of 220 v,calculate the secondary voltage obtained from the transformer .
b. Which type of transformer is this? Draw the model figure of such a transformer.
Identify the type of defect of vision shown in the figure.
The optical disorder illustrated in the diagram is myopia or short-sightedness.
Study the given graph.
A report of blood test of a person is shown in the chart.
Blood Cells | Number of Blood Cells/mm³ |
A | 3,000 |
B | 3,00,000 |
C | 45,00,000 |
Explain IVF process with a suitable figure. Write any two differences between inbreeding and line breeding.
Write any two differences between soap and detergent on the basis of their presence of chemicals and efficiency.
Study the given graph related to the future of the universe.
Write the balanced chemical equation of the reaction between aluminium and dilute sulphuric acid.
Write any two differences between free fall and weightlessness.
Calculate the force of gravitation between the heavenly bodies P and Q on the basis of information given in the figure.
Write the differences between DNA and RNA on the basis of function and structure.
Draw a sex determination chart of the offspring produced by a mother with chromosomes () and father with chromosomes ().
Bee farming (apiculture) is beneficial for the farmers. Clarify with any two points.
Why are Pteridophytes considered to be more developed than Bryophytes? Give any two reasons.
Octopus cannot be kept under phylum Echinodermata even though it is a marine animal. Give any two reasons.