Consider the following statements. 1. Ozone is an allotropic form of oxygen 2. Phosphorus is present in DNA and RNA 3. Halogens occur in free state in nature. 4. The compounds of chlorine are used as cooling agents. The correct statements are: (a) 1 and 4 (b) 2 and 4 (c) 3 and 4 (d) 1 and 2

Consider the following statements. 1. Ozone is an allotropic form of oxygen 2. Phosphorus is present in DNA and RNA 3. Halogens occur in free state in nature. 4. The compounds of chlorine are used as cooling agents. The correct statements are: (a) 1 and 4 (b) 2 and 4 (c) 3 and 4 (d) 1 and 2
by

1 Answer

Answer :

Ans:(d)
by
selected

Related questions

Which one of the following statements concerning elements in the Periodic Table is correct? A Elements of the same group all have the same number of electrons in the outermost occupied electron shell. B Elements of Group 16 occur as cations in ionic compounds. C Oxides of elements in Groups 16 and 17 are basic. D The halogens (Group 17) are all gases at room temperature. E The Group 13 elements are all metals.

Description : Which one of the following statements concerning elements in the Periodic Table is correct? A Elements of the same group all have the same number of electrons in the outermost occupied electron shell. B ... (Group 17) are all gases at room temperature. E The Group 13 elements are all metals.

Last Answer : D) Are compounds that exhibit both metallic & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron

Which of the following statements is not true for retroviruses? (a) DNA is not present at any stage in the life cycle of retroviruses. (b) Retroviruses carry gene(c) The genetic material in mature retroviruses is RNA. (d) Retroviruses are causative agents for certain kinds of cancer in man. for RNA-dependent DNA polymerase.

Description : Which of the following statements is not true for retroviruses? (a) DNA is not present at any stage in the life cycle of retroviruses. (b) Retroviruses carry gene for RNA-dependent DNA ... mature retroviruses is RNA. (d) Retroviruses are causative agents for certain kinds of cancer in man.

Last Answer : (a) DNA is not present at any stage in the life cycle of retroviruses

Nitrogen 1. Is non-essential for the animal bodies 2. In air dilutes oxygen which, otherwise, is very active in the pure form 3. Makes oxygen soluble in blood 4. Is present in DNA and RNA The correct statements are: (a) 1 and 4 only (b) 2 and 4 only (c) 3 and 4 only (d) 1 and 2 only

Description : Nitrogen 1. Is non-essential for the animal bodies 2. In air dilutes oxygen which, otherwise, is very active in the pure form 3. Makes oxygen soluble in blood 4. Is present in DNA and RNA The correct statements are: (a) 1 and 4 only (b) 2 and 4 only (c) 3 and 4 only (d) 1 and 2 only

Last Answer : Ans:(b)

Which of the following halogens does NOT replace the other halogens from their compounds? w) fluorine x) iodine y) bromine z) chlorine

Description : Which of the following halogens does NOT replace the other halogens from their compounds? w) fluorine x) iodine y) bromine z) chlorine

Last Answer : ANSWER: X -- IODINE

Consider the following statements: (1) Copper is present in cytochrome oxidane (2) Pantothenic acid is precursor of co-enzyme-A (3) Thiamine prohosphate is the prosthetic group in decarboxylases (4) Zinc is present in RNA and DNA polymerases

Description : Consider the following statements: (1) Copper is present in cytochrome oxidane (2) Pantothenic acid is precursor of co-enzyme-A (3) Thiamine prohosphate is the prosthetic group in decarboxylases (4) Zinc is present in RNA and DNA polymerases

Last Answer : Ans. ((b))

The most reactive allotropic form of phosphorus is __________ phosphorus. (A) Red (B) Yellow (C) Violet (D) Black

Description : The most reactive allotropic form of phosphorus is __________ phosphorus. (A) Red (B) Yellow (C) Violet (D) Black

Last Answer : (B) Yellow

Consider a compound `CsXY_2` where X and Y are halogens. Which of the following statements is /are correct ? (i)X and Y have different oxidation state

Description : Consider a compound `CsXY_2` where X and Y are halogens. Which of the following statements is /are correct ? (i)X and Y have different oxidation state

Last Answer : Consider a compound `CsXY_2` where X and Y are halogens. Which of the following statements is /are correct ? (i)X ... ) C. Only (ii) D. (i) and (iii)

Allotropic modifications of phosphorus include each of the following EXCEPT: w) red phosphorus x) black phosphorus y) white phosphorus z) green phosphorus

Description : Allotropic modifications of phosphorus include each of the following EXCEPT: w) red phosphorus x) black phosphorus y) white phosphorus z) green phosphorus

Last Answer : ANSWER: Z -- GREEN PHOSPHORUS

Of the nonmetallic elements the one least likely to be found in organic compounds is: w) nitrogen x) phosphorus y) chlorine z) selenium

Description : Of the nonmetallic elements the one least likely to be found in organic compounds is: w) nitrogen x) phosphorus y) chlorine z) selenium

Last Answer : ANSWER: Z -- SELENIUM

Consider the following statements: 1. Gondwana coal is a laminated, bituminous coal. . 2. Gondwana coal is completely free from moisture, sulphur and phosphorus. Which of the statements given above is/are correct? [IAS 2008] (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2

Description : Consider the following statements: 1. Gondwana coal is a laminated, bituminous coal. . 2. Gondwana coal is completely free from moisture, sulphur and phosphorus. Which of the statements given above is/are correct? [IAS 2008] (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2

Last Answer : Ans: (a)

Disinfection of water is done to destroy pathogenic bacteria and thus prevent water-borne diseases. Disinfection of water may be done by the use of (A) Ozone and iodine (B) Chlorine or its compounds (C) Ultraviolet light for irradiation of water (D) All (A), (B) & (C)

Description : Disinfection of water is done to destroy pathogenic bacteria and thus prevent water-borne diseases. Disinfection of water may be done by the use of (A) Ozone and iodine (B) Chlorine or its compounds (C) Ultraviolet light for irradiation of water (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

Which of the following is believed to be responsible for the hole in the ozone layer over Antarctic? w) carbon dioxide x) compounds containing sulfur y) radioactivity z) compounds containing chlorine

Description : Which of the following is believed to be responsible for the hole in the ozone layer over Antarctic? w) carbon dioxide x) compounds containing sulfur y) radioactivity z) compounds containing chlorine  

Last Answer : ANSWER: Z -- COMPOUNDS CONTAINING CHLORINE

The following statement(s) is/are true concerning newer detection methods of systemic infection. a. Enzyme-linked immunosorbent assay (ELISA) is a rapid immunologic assay used for both antigen and antibody detection b. Southern, northern, and western immunoblot techniques are used to detect DNA, RNA, or proteins, respectively c. Polymerase chain reaction (PCR) is a sensitive assay used to detect small amounts of microbial DNA, thus detecting infection at its early stages d. Infectious agents currently detected using advanced molecular techniques include cytomegalovirus (CMV) and human immunodeficiency virus (HIV)

Description : The following statement(s) is/are true concerning newer detection methods of systemic infection. a. Enzyme-linked immunosorbent assay (ELISA) is a rapid immunologic assay used for ... detected using advanced molecular techniques include cytomegalovirus (CMV) and human immunodeficiency virus (HIV)

Last Answer : Answer: a, b, c, d Although the classic detection of infection based on clinical signs of infection and bacterial culture remain the most common clinical tools, increasing ... including CMV and HIV. Furthermore, preliminary investigations into possible detection of fungal pathogens are underway

Pick out the wrong statement. (A) 'Green acid' is the other name of phosphoric acid produced by the reaction of phosphate rock & sulphuric acid (B) Chemically unreactive nature of red phosphorous is due to its polymeric structure (C) Red phosphorous is the most reactive allotropic form of phosphorous (D) Red phosphorous, which is used in the manufacture of safety matches, is converted into white phosphorous by vaporisation followed by condensation

Description : Pick out the wrong statement. (A) 'Green acid' is the other name of phosphoric acid produced by the reaction of phosphate rock & sulphuric acid (B) Chemically unreactive nature of ... in the manufacture of safety matches, is converted into white phosphorous by vaporisation followed by condensation

Last Answer : (C) Red phosphorous is the most reactive allotropic form of phosphorous

Which of the following is Colourless? (1) Chlorine (2) Oxygen (3) Phosphorus (4) Sulphur

Description : Which of the following is Colourless? (1) Chlorine (2) Oxygen (3) Phosphorus (4) Sulphur

Last Answer : (2) Oxygen

Which of the following is colourless ? (1) Chlorine (2) Oxygen (3) Phosphorus (4) Sulphur

Description : Which of the following is colourless ? (1) Chlorine (2) Oxygen (3) Phosphorus (4) Sulphur

Last Answer : Oxygen

Which of the following groups of elements have an OUTER ELECTRONIC configuration of S-2-P-2? w) halogens x) Nitrogen-Phosphorus Group y) Carbon-Silicon Group z) Boron-Aluminum Group

Description : Which of the following groups of elements have an OUTER ELECTRONIC configuration of S-2-P-2? w) halogens x) Nitrogen-Phosphorus Group y) Carbon-Silicon Group z) Boron-Aluminum Group

Last Answer : ANSWER: Y -- CARBON-SILICON GROUP

In genetic engineering, a DNA segment (gene) of interest, is transferred to the host cell through a vector. Consider the following four agents (i-iv) in this regard and select the correct option about which one or more of these can be used as a vector/vectors. (i) Bacterium (ii) Plasmid (iii)Plasmodium (iv) Bacteriophage (a) (i), (ii) and (iv) (b) (i) only (c) (i) and (iii) (d) (ii) and (iv)

Description : In genetic engineering, a DNA segment (gene) of interest, is transferred to the host cell through a vector. Consider the following four agents (i-iv) in this regard and select the correct option about which one or more of these ... ii) and (iv) (b) (i) only (c) (i) and (iii) (d) (ii) and (iv)

Last Answer : (d) (ii) and (iv)

(3) They are not easily combustible Explanation: Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.

Description : (3) They are not easily combustible Explanation: Typical organic compounds are combustible by nature as they contain carbon. Organic compounds mostly consist of carbon, hydrogen, halogen, and phosphorus.

Last Answer : Which of the process is known as nitrification? (1) Reaction of Nitrogen Monoxide with oxygen to form nitric acid (2) Reaction of nitrogen dioxide with water to form nitric acid (3) Conversion of ammonia to nitrites (4) Conversion of nitrite to nitric oxide

The most reactive among the halogens is (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Description : The most reactive among the halogens is (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Last Answer : (1) Fluorine Explanation: Fluorine is one of the most reactive elements in existence, attacking otherwise inert materials such as glass, and forming compounds with the heavier noble gases. It is a ... react with glass in the presence of small amounts of water to form silicon tetrafluoride (SiF4).

The most reactive among the halogens is - (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Description : The most reactive among the halogens is - (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Last Answer : (1) Fluorine Explanation: As a general rule, fluorine is the most reactive halogen and astatine is the least reactive. All halogens form Group 1 salts with similar properties.

The most reactive among the halogens is - (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Description : The most reactive among the halogens is - (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Last Answer : (1) Fluorine Explanation: As a general rule, fluorine is the most reactive halogen and astatine is the least reactive. All halogens form Group 1 salts with similar properties.

Which of the following chemicals are halogens used for disinfection?a. Phenol b. Alcohol c. Detergent d. Chlorine

Description : Which of the following chemicals are halogens used for disinfection? a. Phenol b. Alcohol c. Detergent d. Chlorine

Last Answer : d. Chlorine

The most reactive among the halogens is (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Description : The most reactive among the halogens is (1) Fluorine (2) Chlorine (3) Bromine (4) Iodine

Last Answer : Fluorine

Which element in chlorofluorocarbons (CFCs) is responsible for destroying the Earth's ozone layer? w) oxygen x) fluorine y) chlorine z) bromine

Description : Which element in chlorofluorocarbons (CFCs) is responsible for destroying the Earth's ozone layer? w) oxygen x) fluorine y) chlorine z) bromine

Last Answer : ANSWER: Y -- CHLORINE

Which two gases are used to disinfect water in sewage treatment facilities? w) helium and nitrogen x) ozone and chlorine y) oxygen and hydrogen z) nitrogen and chlorine

Description : Which two gases are used to disinfect water in sewage treatment facilities? w) helium and nitrogen x) ozone and chlorine y) oxygen and hydrogen z) nitrogen and chlorine 

Last Answer : ANSWER: X -- OZONE AND CHLORINE

All of the following statements about RNA-dependent DNA polymerase are true except: (A) It synthesizes DNA using RNA as a template (B) It is also known as reverse transcriptase (C) It synthesizes DNA in 5’→3’ direction (D) It is present in all the viruses

Description : All of the following statements about RNA-dependent DNA polymerase are true except: (A) It synthesizes DNA using RNA as a template (B) It is also known as reverse transcriptase (C) It synthesizes DNA in 5’→3’ direction (D) It is present in all the viruses

Last Answer : Answer : D

Pick out the wrong statement. (A) Yellow phosphorous which is the most reactive allotropic form of phosphorous is transported under water (B) Apatite is the principal material present in phosphate rock which is chemically Ca10 (PO4 )6 (F, Cl, OH) (C) Urea is more hygroscopic than ammonium nitrate (D) Nitrogen fixation means the process of bringing atmospheric nitrogen into combination i.e. into nitrogen compound fo

Description : Pick out the wrong statement. (A) Yellow phosphorous which is the most reactive allotropic form of phosphorous is transported under water (B) Apatite is the principal material present in ... fixation means the process of bringing atmospheric nitrogen into combination i.e. into nitrogen compound fo

Last Answer : (C) Urea is more hygroscopic than ammonium nitrate

In which form is Silicon most frequently found in nature? w) The free element Silicon x) Silicon-Oxygen compounds y) Silicon-Carbon compounds z) Silicon-Metal compounds

Description : In which form is Silicon most frequently found in nature? w) The free element Silicon x) Silicon-Oxygen compounds y) Silicon-Carbon compounds z) Silicon-Metal compounds

Last Answer : ANSWER: X -- SILICON-OXYGEN COMPOUNDS

Consider the following compounds : (i) sulpher dioxide (ii) hydrogen peroxide (iii) ozone Among these compounds, those which can act as bleaching agen

Description : Consider the following compounds : (i) sulpher dioxide (ii) hydrogen peroxide (iii) ozone Among these compounds, those which can act as bleaching agen

Last Answer : Consider the following compounds : (i) sulpher dioxide (ii) hydrogen peroxide (iii) ozone Among these compounds, those ... C. 1 and 2 D. 1, 2 and 3

Consider the following compounds : (i) sulpher dioxide (ii) hydrogen peroxide (iii) ozone Among these compounds, those which can act as bleaching agen

Description : Consider the following compounds : (i) sulpher dioxide (ii) hydrogen peroxide (iii) ozone Among these compounds, those which can act as bleaching agen

Last Answer : Consider the following compounds : (i) sulpher dioxide (ii) hydrogen peroxide (iii) ozone Among these compounds, those ... C. 1 and 2 D. 1, 2 and 3

What compounds are only found in RNA? DNA?

Description : What compounds are only found in RNA? DNA?

Last Answer : Is this a homework question?

Excluding Astatine, which halogen does NOT replace the other halogens from their compounds?

Description : Excluding Astatine, which halogen does NOT replace the other halogens from their compounds?

Last Answer : ANSWER: IODINE

(1) the action of ultraviolet rays on oxygen Explanation: The majority of tropospheric ozone formation occurs when nitrogen oxides (NOx), carbon monoxide (CO ) and volatile organic compounds (VOCs), such as xylene, react in the atmosphere in the presence of sunlight containing ultra violet rays. NOx, CO, and VOCs are called ozone precursors. CO + 2O2 + CO2 + O3

Description : (1) the action of ultraviolet rays on oxygen Explanation: The majority of tropospheric ozone formation occurs when nitrogen oxides (NOx), carbon monoxide (CO ) and volatile organic compounds (VOCs), such as xylene, ... violet rays. NOx, CO, and VOCs are called ozone precursors. CO + 2O2 + CO2 + O3

Last Answer : Water is not effective in extinguishing a fire caused by petrol because - (1) the flame is too hot for water to cool it down (2) water and petrol react chemically (3) water and petrol are ... (4) water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn

Which of the following statements about nucleic acid is most correct? (A) Both pentose nucleic acid and deoxypentose nucleic acid contain the same pyrimidines (B) Both pentose nucleic acid and deoxypentose nucleic acid and deoxypentose nucleic acid Contain the same purines (C) RNA contains cytosine and thymine (D) DNA and RNA are hydrolysed by weak alkali

Description : Which of the following statements about nucleic acid is most correct? (A) Both pentose nucleic acid and deoxypentose nucleic acid contain the same pyrimidines (B) Both pentose nucleic acid and deoxypentose ... (C) RNA contains cytosine and thymine (D) DNA and RNA are hydrolysed by weak alkali

Last Answer : Answer : B

Which one of the following statements about viruses is correct? (a) Viruses possess their own metabolic system. (b) All viruses contain both RNA and DNA. (c) Viruses are obligate parasites. (d) Nucleic acid of viruses is known as capsid.

Description : Which one of the following statements about viruses is correct? (a) Viruses possess their own metabolic system. (b) All viruses contain both RNA and DNA. (c) Viruses are obligate parasites. (d) Nucleic acid of viruses is known as capsid.

Last Answer : (c) Viruses are obligate parasites.

The only correct statement about oncoviruses is (A) All the oncoviruses are RNA viruses (B) Reverse transcriptase is present in all oncoviruses (C) Viral oncogenes are identical to human protooncogens (D) Both DNA and RNA viruses can be oncoviruses

Description : The only correct statement about oncoviruses is (A) All the oncoviruses are RNA viruses (B) Reverse transcriptase is present in all oncoviruses (C) Viral oncogenes are identical to human protooncogens (D) Both DNA and RNA viruses can be oncoviruses

Last Answer : Answer : D

Francis Crick’s seminal concept that in nature genetic information generally flows from DNA to RNA to protein.

Description : Francis Crick’s seminal concept that in nature genetic information generally flows from DNA to RNA to protein.

Last Answer : Ans. Central Dogma

Which one of the following features is absent in a virus ? (1) reproduce within host cell (2) presence of cell wall (3) fully parasitic in nature (4) presence of either DNA or RNA

Description : Which one of the following features is absent in a virus ? (1) reproduce within host cell (2) presence of cell wall (3) fully parasitic in nature (4) presence of either DNA or RNA

Last Answer : presence of cell wall 

In human body, the cell growth and differentiation are highly controlled and regulated, but in cancer cells. (a) there is breakdown of these regulatory mechanism leading to formation of benign and malignant tumors (b) controlled cell division and over production of genetic material occur (c) RNA is mutated and produced in less amount (d) DNA is mutated and produced in less amount

Description : In human body, the cell growth and differentiation are highly controlled and regulated, but in cancer cells. (a) there is breakdown of these regulatory mechanism leading to formation of benign and malignant ... is mutated and produced in less amount (d) DNA is mutated and produced in less amount

Last Answer : Ans:(a)

Which of the following elements does not normally occur as a diatomic molecule? w) hydrogen x) chlorine y) argon z) oxygen

Description : Which of the following elements does not normally occur as a diatomic molecule? w) hydrogen x) chlorine y) argon z) oxygen

Last Answer : ANSWER: Y -- ARGON

Which one of the following is common between prokaryotic and eukaryotic chromosomes? a. Presence or absence of introns. b. Loop or linear chromosomes. c. Genetic recombination occurrence in RNA. d. Mutations occur in the DNA.

Description : Which one of the following is common between prokaryotic and eukaryotic chromosomes? a. Presence or absence of introns. b. Loop or linear chromosomes. c. Genetic recombination occurrence in RNA. d. Mutations occur in the DNA.

Last Answer : d. Mutations occur in the DNA.

Do displacement reactions only occur between halogens?

Description : Do displacement reactions only occur between halogens?

Last Answer : Also other elements can be involved.

(a) Define a balanced chemical equation. Why should an equation be balanced? (b) Write the balanced chemical equation for the following reaction: (i) Phosphorus burns in presence of chlorine to form phosphorus penta chloride. (ii) Burning of natural gas. (iii) The process of respiration. -Chemistry

Description : (a) Define a balanced chemical equation. Why should an equation be balanced? (b) Write the balanced chemical equation for the following reaction: (i) Phosphorus burns in presence of chlorine to form phosphorus penta chloride. (ii) Burning of natural gas. (iii) The process of respiration. -Chemistry

Last Answer : Answer. (a) Balanced chemical equation has an equal number of atoms of different elements in the reactants and products. According to law of conservation of mass, matter can neither be created nor be destroyed in a chemical ... C6H12O6 (s) + 6O2 (g) + 6H2O ---> 6CO2 (aq) + 12H2O (l) + energy

When the Exxon Valdez oil spill occurred, technologists "fertilized" the oil-soaked water with _____ to modify the environment and stimulate he growth of naturally occurring microorganisms. a. nitrogen sources (e.g., urea) b. phosphorus compounds c. other mineral nutrients d. A-C above are correct

Description : When the Exxon Valdez oil spill occurred, technologists "fertilized" the oil-soaked water with _____ to modify the environment and stimulate he growth of naturally occurring microorganisms. a. nitrogen sources (e.g., urea) b. phosphorus compounds c. other mineral nutrients d. A-C above are correct

Last Answer : d. A-C above are correct

Consider the following statements : 1. Agricultural soils release nitrogen oxides into environment. 2. Cattle release ammonia into environment. 3. Poultry industry releases reactive nitrogen compounds into environment. Which of the statements given above is/ are correct? a) 1 and 3 only b) 2 and 3 only c) 2 only d) 1, 2 and 3

Description : Consider the following statements : 1. Agricultural soils release nitrogen oxides into environment. 2. Cattle release ammonia into environment. 3. Poultry industry releases reactive nitrogen compounds into environment. Which of the statements ... and 3 only b) 2 and 3 only c) 2 only d) 1, 2 and 3

Last Answer : d) 1, 2 and 3

Viruses are no more “alive” than isolated chromosomes because (a) they require both RNA and DNA (b) they both need food molecules (c) they both require oxygen for respiration (d) both require the environment of a cell to replicate.

Description : Viruses are no more “alive” than isolated chromosomes because (a) they require both RNA and DNA (b) they both need food molecules (c) they both require oxygen for respiration (d) both require the environment of a cell to replicate.

Last Answer : (d) both require the environment of a cell to replicate.

Which gas is used in the preparation of soft drinks? A. Oxygen B. Carbon dioxide C. Nitrogen D. Halogens

Description : Which gas is used in the preparation of soft drinks? A. Oxygen B. Carbon dioxide C. Nitrogen D. Halogens

Last Answer : ANSWER: B

Which gas is used in the preparation of soft drinks? A. Oxygen B. Carbon dioxide C. Nitrogen D. Halogens

Description : Which gas is used in the preparation of soft drinks? A. Oxygen B. Carbon dioxide C. Nitrogen D. Halogens

Last Answer : ANSWER: B

Which gas is used in the preparation of soft drinks? A. Oxygen B. Carbon dioxide C. Nitrogen D. Halogens

Description : Which gas is used in the preparation of soft drinks? A. Oxygen B. Carbon dioxide C. Nitrogen D. Halogens

Last Answer : ANSWER: B