Complete and balance the following chemical equations:
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Solution and Explanation
Complete and Balanced Chemical Equations
(1) Thermal Decomposition of Potassium Permanganate: \[ 2KMnO_4 \xrightarrow{\text{heat}} K_2MnO_4 + MnO_2 + O_2 \] (2) Dichromate-Iodide Reaction: \[ Cr_2O_7^{2-} + 6I^- + 14H^+ \rightarrow 2Cr^{3+} + 3I_2 + 7H_2O \]
Top Questions on Solutions
According to the generally accepted definition of the ideal solution there are equal interaction forces acting between molecules belonging to the same or different species. (This is equivalent to the statement that the activity of the components equals the concentration.) Strictly speaking, this concept is valid in ecological systems (isotopic mixtures of an element, hydrocarbons mixtures, etc.). It is still usual to talk about ideal solutions as limiting cases in reality since very dilute solutions behave ideally with respect to the solvent. This law is further supported by the fact that Raoult’s law empirically found for describing the behaviour of the solvent in dilute solutions can be deduced thermodynamically via the assumption of ideal behaviour of the solvent.
Answer the following questions:
(a) Give one example of miscible liquid pair which shows negative deviation from Raoult’s law. What is the reason for such deviation?
(b) (i) State Raoult’s law for a solution containing volatile components.
OR
(ii) Raoult’s law is a special case of Henry’s law. Comment.
(c) Write two characteristics of an ideal solution.- A solution of glucose (molar mass = 180 g mol\(^{-1}\)) in water has a boiling point of 100.20°C. Calculate the freezing point of the same solution. Molal constants for water \(K_f\) and \(K_b\) are 1.86 K kg mol\(^{-1}\) and 0.512 K kg mol\(^{-1}\) respectively.
- Define Azeotrope. What type of Azeotrope is formed by negative deviation from Raoult's law? Give an example.
- Give reasons:
(a) Cooking is faster in a pressure cooker than in an open pan.
(b) On mixing liquid X and liquid Y, volume of the resulting solution decreases. What type of deviation from Raoult's law is shown by the resulting solution? What change in temperature would you observe after mixing liquids X and Y? - An unripe mango placed in a concentrated salt solution to prepare pickle, shrivels because __________
Questions Asked in CBSE CLASS XII exam
- If \( P(A) = \frac{1}{5}, P(B) = \frac{3}{5} \) and \( P(A \cap B) = \frac{2}{5} \), then \( P(A' \cup B') \) is :
- CBSE CLASS XII - 2025
- Probability
- Chandan, Deepak and Elvish were partners in a firm sharing profits and losses in the ratio of 1 : 2 : 2. Their Balance Sheet as at 31st March, 2024 stood as follows:
Balance Sheet of Chandan, Deepak and Elvish as at 31st March, 2024
Chandan retired from the firm on 1st April, 2024 on the following terms:Liabilities Amount (₹) Assets Amount (₹) Capitals: Fixed Assets 27,00,000 Chandan 7,00,000 Stock 3,00,000 Deepak 5,00,000 Debtors 2,00,000 Elvish 3,00,000 Cash 1,00,000 General Reserve 4,50,000 Creditors 13,50,000 Total 33,00,000 Total 33,00,000
[(i)] Fixed assets were to be depreciated by 10%.
[(ii)] Debtors of ₹ 30,000 were to be written off as bad debts.
[(iii)] Goodwill of the firm was valued at ₹ 6,00,000 and the retiring partner’s share is adjusted through the capital accounts of the remaining partners.
[(iv)] Chandan was paid through cash brought in by Deepak and Elvish in such a way so as to make their capitals proportionate to their new profit sharing ratio. Prepare Revaluation Account and Partners’ Capital Accounts. A coil of 60 turns and area \( 1.5 \times 10^{-3} \, \text{m}^2 \) carrying a current of 2 A lies in a vertical plane. It experiences a torque of 0.12 Nm when placed in a uniform horizontal magnetic field. The torque acting on the coil changes to 0.05 Nm after the coil is rotated about its diameter by 90°. Find the magnitude of the magnetic field.
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- Magnetism and matter
- ‘A thing of beauty is a joy forever.’ Explain with reference to the poem. (A Thing of Beauty)
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- Literature
- A voltmeter of resistance 1000 \( \Omega \) can measure up to 25 V. How will you convert it so that it can read up to 250 V?
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- Units and measurement