Very Short Answer Based Questions
Q1: What is the
common name of the buccal cavity?
Q2: Name the enzyme present in
saliva?
Q3: Which organ releases gastric juice?
Q4: Name
the digestive juice(s) the small intestine receives.
Q5: Name
the largest digestive gland.
Q6: What is the length of the small
intestine in a human adult?
Class 10 is a crucial turning point in a student's academic career, and passing the CBSE exams depends on possessing the correct reference books.
When choosing science books for standard 10 students, it is important to consider a few key factors, including the level of difficulty, relevance to the curriculum, and engagement level. Here are some tips to help you choose the best science books for standard 10 students:
Question: What are different types of chemical reactions?
Answer:
There are several different types of chemical reactions, including:
Study the following case study and answer the questions given below:
Water is a simple molecule consisting of one oxygen atom bonded to two different hydrogen atoms. Because of the higher electronegativity of the oxygen atom, the bonds are polar covalent (polar bonds). The oxygen atom attracts the shared electrons of the covalent bonds to a significantly greater extent than the hydrogen atoms. The molecule has a bent structure, the H—O—H bond angle is about 105°.
Q1. In which of the following, heat energy will be evolved?
(a) Electrolysis of water
(b) Dissolution of NH4Cl in water
(c) Burning of L.P.G.
(d) Decomposition of AgBr in the presence of sunlight
Q1. What is oxidation?
Answer: Addition of oxygen or removal of hydrogen from a compound is known as oxidation.
Elements or compounds in which oxygen or non-metallic element is added or hydrogen or metallic element is removed are called to be oxidized.
1. At present about 118 elements are known.
2. Elements can be divided into two main groups: metals and non-metals.
3. Elements which form positive ions by losing electrons are called metals. Thus, metals are the elements which have the tendency to lose electrons.
In this video and subsequent videos, we will focus on Acids and its properties. We'll learn about
- What are Acids?
- What is the role of acid in our life?
- How acids are classified?
CBSE Syllabus for Academic Year 2022-23 is available here.
CH-1: Chemical Reactions and Equations
Deleted- Corrosion and Rancidity (Pg-13)
CH-2: Acids, Bases and Salts
No Reduction
Here is a list of important differences related to the Asexual mode and the Sexual Mode of reproduction, commonly asked in examinations.
Binary Fission vs Multiple Fission
Please note the Board will conduct the annual scheme of assessment at the end of the Academic Session 2022-23
Class 9 Science
Deleted Chapters:
- DIVERSITY IN LIVING ORGANISMS
- NATURAL RESOURCES
- WHY DO WE FALL ILL?
Chapter: NATURAL RESOURCES will be taught in the class and students are encouraged to prepare a brief write up on any concept of this chapter in their Portfolio (internal assessment)
Fill in the blanks with suitable word(s).
1. The generation resulting immediately from a cross of the first set of parents is called ____________.
2. All cells forming the body of an organism, except the reproductive cells are called _________ cells.
3. A type of crossing in which only one pair of contrasting characters is considered is called _________ cross.
Maximum Marks: 50 (40 Theory Paper + 10 Marks Internal Assessment)
Duration: 2 Hours
Weightage Per Paper:
Physics: 12 Marks
Chemistry: 10 Marks
Biology: 18 Marks
Q1: What is the atomic number of a carbon atom?
Answer: 6
Q2: How many valence electrons are present in a carbon atom?
Answer: 4 (electronic configuration is K:2 L:4)
Q3: What are allotropes?
Answer: The property due to which one element exists in more than one form, which differs in physical properties but has similar chemical properties. These forms of an element are called allotropes.
Q1: The laws of reflection hold true for:
(a) plane mirrors only
(b) concave mirrors only
(c) convex mirrors only
(d) all reflecting surfaces
Q2: Focal length of a plane mirror is
(a) zero
(b) infinite
(c) 25 cm
(d) -25 cm
Q1: Which activity is basic to living beings?
(a) Reproduction
(b) Locomotion
(c) Molecular Movement
(d) Adaptation
Fill in the blanks with suitable words
1. An acid is a compound which when dissolved in water gives _________ ions as the only _________ ions.
2. Higher the pH value of a solution, the more __________ it is.
3. pH value of lemon juice is _________ than 7.
Salts/Compounds Colour
1. Potassium dichromate, K₂Cr₂O₇ Orange
2. Potassium permanganate, KMnO₄ Violet
3. Ferric tetra-oxide, Fe₃O₄ Black
4. Ferrous sulphate, FeSO₄.7H₂O Green
5. Ferric sulphate, Fe₂(SO₄)₃ Yellow
6. Ferric hydroxide, Fe(OH)₂ Green
Q1: By what other name is the unit joule/coulomb called ?
Answer: Volt
Q2: Which of the following statements correctly defines a volt ?
(a) a volt is a joule per ampere.
(b) a volt is a joule per coulomb.
Answer: (b) a volt is a joule per coulomb.
Q3: (a) What do the letters p.d. stand for ?
(b) Which device is used to measure p.d. ?
Answer:
(a) p.d. stands for potential difference.
(b) Voltmeter is used to measure p.d.
Chapter: Life Processes (NCERT Book Activity 6.1)
Activity Steps
Step 1: Take a potted plant with variegated leaves – for example, a money plant or croton.
Step 2: Keep the plant in a dark room for three days so that all the starch gets used up.
Step 3: Now keep the plant in sunlight for about six hours.
Step 4: Pluck a leaf from the plant. Mark the green areas in it and trace them on a sheet of paper.
Step 5: Dip the leaf in boiling water for a few minutes.
Step 6: After this, immerse it in a beaker containing alcohol.
Step 7: Carefully place the above beaker in a water bath and heat till the alcohol begins to boil.
What happens to the colour of the leaf? What is the colour of the solution?
Step 8: Now dip the leaf in a dilute solution of iodine for a few minutes.
Take out the leaf and rinse off the iodine solution.
Observe the colour of the leaf and compare this with the tracing of the leaf done in the beginning.
What can you conclude about the presence of starch in various areas of the leaf?
