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Prisha Laxmi
@prisha-laxmi
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Joined: Mar 13, 2022
Last seen: May 1, 2022
Topics: 0 / Replies: 163
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Answer to: Phosphate fertilizers when added to water leads to

Correct answer: (d) nutrient enrichment (eutrophication). Explanation: Addition of phosphate fertilizers to water leads to nutrient enrichment (eu...

3 years ago
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Answer to: The false statement among the following: (a) The average residence time of NO is one month. (b) Limestone acts as a sink for SOx.

Correct answer: (a) The average residence time of NO is one month. Explanation: The average residence time of NO is 4 days.

3 years ago
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Answer to: Which of the following is the major cause of global warming?

Correct answer: (b) re-radiation of I.R. rays by CO2 and H2O.

3 years ago
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Answer to: Which of the following is/are the hazardous pollutant(s) present in automobile exhaust gases?

Correct answer: (c) (ii) and (iv) Explanation: CO and oxides of Nitrogen are poisonous gases present in automobile exhaust gases.

3 years ago
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Answer to: Identify the pollutant gases largely responsible for the discoloured and lustreless nature of marble of the Taj Mahal?

Correct answer: (c) SO2 and NO2 Explanation: SO2 and NO2 are responsible for the discoloured and lusterless nature of marble.

3 years ago
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Answer to: Soil is polluted by I. pesticides II. synthetic fertilizers III. green manure

Correct answer: (b) I and II Explanation: Pesticides and synthetic fertilizers pollute the soil.

3 years ago
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Answer to: Excess nitrate in drinking water can cause

Correct answer: (a) methemoglobinemia Explanation: Excessive concentration of nitrate in drinking water is harmful and can cause methemoglobinemia...

3 years ago
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Answer to: Which of the following statements about the depletion of ozone layer is correct?

Correct answer: (c) Freons, chlorofluorocarbons, are inert. Chemically, they do not react with ozone in stratosphere. Explanation: Freons and chlo...

3 years ago
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Answer to: Global warming is due to increase of: (a) methane and nitrous oxide in atmosphere. (b) methane and CO2 in atmosphere.

Correct answer: (b) methane and CO2 in atmosphere. Explanation: The main gas responsible for the global warming is carbon dioxide. Other contribut...

3 years ago
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Answer to: Which of the following acts as a sink for CO? (a) Plants (b) Haemoglobin

Correct answer: (c) Microorganisms present in the soil Explanation: CO is converted into CO2 by microorganism present in soil.

3 years ago
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Answer to: Which of the following statement is false? (a) London smog is oxidising in nature (b) Photochemical smog causes irritation in eyes

Correct answer: (a) London smog is oxidising in nature Explanation: London smog is reducing in nature.

3 years ago
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Answer to: Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following points:

(i) In the 1st, 2nd and 3rd transition series, the 3d, 4d and 5d orbitals are respectively filled. We know that elements in the same vertical column g...

3 years ago
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Answer to: What can be inferred from the magnetic moment values of the following complex species? Example Magnetic Moment (BM)

Magnetic moment (μ) is given as μ = For value n = 1, μ = = = 1.732 For value n = 2, μ = = = 2.83 For value n = 3, μ = = = 3.87 For valu...

3 years ago
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Answer to: Comment on the statement that elements of the first transition series possess many properties different from those of heavier transition elements.

The properties of the elements of the first transition series differ from those of the heavier transition elements in many ways. (i) The atomic siz...

3 years ago
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Answer to: Write the electronic configurations of the elements with the atomic numbers 61, 91, 101, and 109.

Atomic number - Electronic configuration 61 → [Xe]544f55d06s2 91 → [Rn]865f26d17s2 101 ...

3 years ago
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Answer to: Compare the chemistry of the actinoids with that of lanthanoids with reference to: (i) electronic configuration (ii) oxidation states and (iii) chemical reactivity.

Electronic configuration The general electronic configuration for lanthanoids is [Xe]544f0-145d0-16s2 and that for actinoids is [Rn]865f1-146d0-17s...

3 years ago
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Answer to: Name the members of the lanthanoid series which exhibit +4 oxidation state and those which exhibit +2 oxidation state. Try to correlate this type of behavior with the electronic configurations of these elements.

The lanthanides that exhibit +2 and +4 states are shown in the given table. The atomic numbers of the elements are given in the parenthesis. +2 → ...

3 years ago
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Answer to: Use Hund's rule to derive the electronic configuration of Ce^3+ ion and calculate its magnetic moment on the basis of 'spin-only' formula.

Ce: 1s22s22p63s23p63d104s24s24p64p64d105s25p64f15d16s2 Magnetic moment can be calculated as: μ = Where, n = number of unpaired electrons Th...

3 years ago
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Answer to: Which is the last element in the series of actinoids? Write the electronic configuration of this element. Comment on the possible oxidation state of this element.

The last element in the actinoid series is lawrencium, Lr. Its atomic number is 103 and its electronic configuration is [Rn]5f146d17s2. The most commo...

3 years ago
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Answer to: The chemistry of the actinoid elements is not so smooth as that of the Lanthanoids. Justify this statement by giving some examples from the oxidation state of these elements.

Lanthanoids primarily show three oxidation states (+2, +3, +4). Among these oxidation states, +3 state is the most common. Lanthanoids display a limit...

3 years ago
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