A solution contains Na 2​ CO 3​ and NaHCO 3​ . 10 mL of the solution required 2.5 mL of 0.1 M H 2​ SO 4​ for neutralisation using phenolphthalein as indicator. Methyl orange is then added when a further 2.5 mL of 0.2 M H 2​ SO 4​ was required. Calculate the amount of Na 2​ CO 3​ and NaHCO 3​ in one litre of the solution.

100mL of a water sample contains 0.81g of calcium bicarbonate and 0.73 of magnesium bicarbonate. The hardness of this water sample expressed in terms of equivalents of CaCO 3​ is:(molar mass of calcium bicarbonate is 162g mol^−1 and magnesium bicarbonate is 146 gmol −1 )

(A) 1000 ppm

(B) 10000 ppm

(C) 100 ppm

(D) 5000 ppm

Solution :

neq​.CaCO3​=neq​Ca(HCO3​)2​+neq​Mg(HCO3​)2​

or 

(W​÷100) ×2 = (0.81​÷ 162)×2 + (0.73÷146)​×2 

∴w=1.0

∴ Hardness=(1.0÷100) ×10^6=10000ppm

Hence correct option is (B) 10000ppm

Write the POAC equations for all the atoms in the following reaction.

Illustrative solution:

Applying POAC on (P) atoms:

                                                    P à H₃PO₄

Numbers of moles of (P) atoms in P₄ = Numbers of moles of (P) atoms in H₃PO₄

                                               4x nP₄= 1x nH₃PO₄

Applying POAC on (H) atoms:

                                       1x nHNO3 = 3 x nH₃PO₄ + 2 x nH₂O

Applying POAC on (N) atoms:

                                       1 x nHNO₃ = 1 x nNO₂

Applying POAC on (O) atoms:

                                       3 x nHNO₃ = 4 x nH₃PO₄ +2 x nNO₂ + 1nH₂O

Related Questions:

Principle of atom conservation (PAOC):

Illustrative example (2) 27.6 gm K2CO3 (138) was treated by a series of reagents so as to convert all its carbon into K2Zn3[Fe(CN)6]2(MM=698) Calculate mass of K2Zn3[Fe(CN)6]2.

Illustrative example (3)0.32 gm mole of LiAlH4 in ether solution was placed in a flask and 74 gm (1 mole ) of t- butyl alcohol was added . The product is LiAlHC12H27O3. Calculate mass of product if all lithium atoms are converted.

Illustrative example (4) All the carbon atom present in KH3(C2O4)2.2H2O weighting 254 gm is converted to CO2. How many gram of CO2 were obtained.

Illustrative example (5) For BaCl2.XH2O , 2.1 gm of Compound gives 2 gm of anhydrous BaSO4 (M.mass =233)upon treatment with H2SO4 then calculate value of X.

Illustrative example (6) In a determination of P an aqueous solution of NaH2PO4 is treated with a mixture of Ammonium and magnesium ions to precipitate magnesium Ammonium phosphate (Mg(NH4)PO4.6H2O. This is heated and decomposed to magnesium pyrophosphate. Which is weighed. A solution of NaH2PO4 yield 3.33 gm of Mg2P2O7. What is weighed of NaH2PO4 was present originally.

In a determination of P an aqueous solution of NaH2PO4 is treated with a mixture of Ammonium and magnesium ions to precipitate magnesium Ammonium phosphate (Mg(NH4)PO4.6H2O. This is heated and decomposed to magnesium pyrophosphate. Which is weighed. A solution of NaH2PO4 yield 3.33 gm of Mg2P2O7. What is weighed of NaH2PO4 was present originally.

Related Questions:

Principle of atom conservation (PAOC):

Illustrative example (2) 27.6 gm K2CO3 (138) was treated by a series of reagents so as to convert all its carbon into K2Zn3[Fe(CN)6]2(MM=698) Calculate mass of K2Zn3[Fe(CN)6]2.

Illustrative example (3)0.32 gm mole of LiAlH4 in ether solution was placed in a flask and 74 gm (1 mole ) of t- butyl alcohol was added . The product is LiAlHC12H27O3. Calculate mass of product if all lithium atoms are converted.

Illustrative example (4) All the carbon atom present in KH3(C2O4)2.2H2O weighting 254 gm is converted to CO2. How many gram of CO2 were obtained.

Illustrative example (5) For BaCl2.XH2O , 2.1 gm of Compound gives 2 gm of anhydrous BaSO4 (M.mass =233)upon treatment with H2SO4 then calculate value of X.

For BaCl2.XH2O , 2.1 gm of Compound gives 2 gm of anhydrous BaSO4 (M.mass =233)upon treatment with H2SO4 then calculate value of X.

 

Related Questions:

Principle of atom conservation (PAOC):

Illustrative example (2) 27.6 gm K2CO3 (138) was treated by a series of reagents so as to convert all its carbon into K2Zn3[Fe(CN)6]2(MM=698) Calculate mass of K2Zn3[Fe(CN)6]2.

Illustrative example (3)0.32 gm mole of LiAlH4 in ether solution was placed in a flask and 74 gm (1 mole ) of t- butyl alcohol was added . The product is LiAlHC12H27O3. Calculate mass of product if all lithium atoms are converted.

Illustrative example (4) All the carbon atom present in KH3(C2O4)2.2H2O weighting 254 gm is converted to CO2. How many gram of CO2 were obtained.

All the carbon atom present in KH3(C2O4)2.2H2O weighting 254 gm is converted to CO2. How many gram of CO2 were obtained.

 Illustrative solution:

Related Questions:

Principle of atom conservation (PAOC):

Illustrative example (2) 27.6 gm K2CO3 (138) was treated by a series of reagents so as to convert all its carbon into K2Zn3[Fe(CN)6]2(MM=698) Calculate mass of K2Zn3[Fe(CN)6]2.

Illustrative example (3)0.32 gm mole of LiAlH4 in ether solution was placed in a flask and 74 gm (1 mole ) of t- butyl alcohol was added . The product is LiAlHC12H27O3. Calculate mass of product if all lithium atoms are converted.

0.32 gm mole of LiAlH4 in ether solution was placed in a flask and 74 gm (1 mole ) of t- butyl alcohol was added . The product is LiAlHC12H27O3. Calculate mass of product if all lithium atoms are converted.

Illustrative solution:

By applying POAC on (C) atoms:

Related Questions:

Principle of atom conservation (PAOC):

Illustrative example (2) 27.6 gm K2CO3 (138) was treated by a series of reagents so as to convert all its carbon into K2Zn3[Fe(CN)6]2(MM=698) Calculate mass of K2Zn3[Fe(CN)6]2.

Illustrative example (3) All the carbon atom present in KH3(C2O4)2.2H2O weighting 254 gm is converted to CO2. How many gram of CO2 were obtained.

Illustrative example (4) For BaCl2.XH2O , 2.1 gm of Compound gives 2 gm of anhydrous BaSO4 (M.mass =233)upon treatment with H2SO4 then calculate value of X.

Illustrative example (5) In a determination of P an aqueous solution of NaH2PO4 is treated with a mixture of Ammonium and magnesium ions to precipitate magnesium Ammonium phosphate (Mg(NH4)PO4.6H2O. This is heated and decomposed to magnesium pyrophosphate. Which is weighed. A solution of NaH2PO4 yield 3.33 gm of Mg2P2O7. What is weighed of NaH2PO4 was present originally.

27.6 gm K2CO3 (138) was treated by a series of reagents so as to convert all its carbon into K2Zn3[Fe(CN)6]2(MM=698) Calculate mass of K2Zn3[Fe(CN)6]2.

 Here all the carbon of K2CO3 converted into a complex hence POAC can apply

Related Questions:

Illustrative example (2)0.32 gm mole of LiAlH4 in ether solution was placed in a flask and 74 gm (1 mole ) of t- butyl alcohol was added . The product is LiAlHC12H27O3. Calculate mass of product if all lithium atoms are converted.

Illustrative example (3) All the carbon atom present in KH3(C2O4)2.2H2O weighting 254 gm is converted to CO2. How many gram of CO2 were obtained.

Illustrative example (4) For BaCl2.XH2O , 2.1 gm of Compound gives 2 gm of anhydrous BaSO4 (M.mass =233)upon treatment with H2SO4 then calculate value of X.

Illustrative example (5) In a determination of P an aqueous solution of NaH2PO4 is treated with a mixture of Ammonium and magnesium ions to precipitate magnesium Ammonium phosphate (Mg(NH4)PO4.6H2O. This is heated and decomposed to magnesium pyrophosphate. Which is weighed. A solution of NaH2PO4 yield 3.33 gm of Mg2P2O7. What is weighed of NaH2PO4 was present originally.

A plant virus is found to consist to uniform cylindrical particles of 150Å in diameter and 5000Å long. The specific volume of the virus is 0.75 cm3/g. What is the molecular mass of virus ?

 

Related Questions:

Calculate the amount of 80 % pure NaOH sample required to react with 21.3 gm Chlorine in hot condition.

When 1.25 gm sample of Chalk is strongly heated. 0.44 gm of CO2 is produced. Calculate % purity of Chalk sample?

The Mass of 80% pure H2SO4 required to completely neutralize 106 gm of Na2CO3?

When dilute HCl is added to 5.73 gm of contaminated CaCO3, 2.49 gm of CO2 is obtained. Find % purity of CaCO3 sample?

200 gm of CaCO3 sample on heating produces 11.2 liters of CO2 (g) at STP. Calculate % purity of CaCO3 sample?

A sample of impure Iron pyrite (FeS2) when 13.9 gm heated then it produces iron (iii) oxide (Fe2O3) and Sulphur dioxide (SO2). If 8.02 gm Iron (iii) oxide is obtained, what was the % purity of given sample (original-FeS2)?

Galena (an ore) is partially oxidized by passing air through it at high temperature. After some time, the passage of air is stopped, but the heating is continued in a closed furnance such that the contents undergo self-reduction. The weight (in kg) of Pb produced per kg of O2 consumed is______ . (Atomic weights in g mol–1 : O = 16, S = 32, Pb = 207). (JEE-Advanced 2018 Paper-2)

P and Q are two elements which from P2Q3 and PQ2. if 0.15 mole of P2Q3 weighs 15.9 gm and 0.15 mole of PQ2 weighs 9.3 gm, then, what weights of P and Q?

367.5 gm KClO3 (122.5) when heated then calculate. (1) How many gram of O2 is produced? (2) How Many litre of O2 is produced at STP?

How many moles O2 are required to needed produced 5 moles of Fe2O3.

How many grams of Fe2O3 formed by heating of 18 gm FeO with O2.

If 4 gm of bleaching powder dissolved to give 100 ml solution 25 ml of it react with excess of CH3COOH and KI .The Iodine liberation required 10 ml of 0.125 N Hypo solutions. Calculate % of available chlorine in the sample.

25 ml of household bleach solution was mixed with 30 ml of 0.50 M KI and 10 ml of 4.0N acetic acid. In this titration of the liberated iodine 48 ml of 0.25 N Na2S2O3 was used to reach the end point. The Molarity of household bleach solution is?

25 ml of household bleach solution was mixed with 30 ml of 0.50 M KI and 10 ml of 4.0N acetic acid. In this titration of the liberated iodine 48 ml of 0.25 N Na2S2O3 was used to reach the end point. The Molarity of household bleach solution is?

Calculate the % of available chlorine in the sample in a sample of 3.35 gm of bleaching powder which was dissolved to 100 ml water. 25 ml of this solution on treatment react with KI and dilute acid. Required 20 ml 0.125 N Hypo solution (Sodiumthiosulphate- Na2S2O3).

Related Questions:

(1) What are the Antichlor ?

(2) If 4 gm of bleaching powder dissolved to give 100 ml solution 25 ml of it react with excess of CH3COOH and KI .The Iodine liberation required 10 ml of 0.125 N Hypo solutions. Calculate % of available chlorine in the sample.

PERCENTAGE (%) AVAILABLE CHLORINE IN BLEACHING POWDER:

 

What are the Antichlor ?

An antichlor  is a substance used to decompose residual hypochlorite or chlorine after use of chlorine based bleaching , in order to prevent ongoing reactions .example s of antichlor – Sodiumbisulphite (NaHSO₃), Pottassiumbisulphite (KHSO₃) ,  Sodiummetasulphite (Na₂S₂O₃), Sodiumthiosulphate  (Na₂S₂O₃) and hydrogen peroxide (H₂O₂).

If trace of chlorine are not remove from pulp used for paper manufacturing,then on the long standing it weaken the paper and makes it yellowish. 

Related topics: 

Mole concept and Stiochiometry

MOLE-MOLE ANALYSIS

 CONCEPT OF LIMITING REAGENTS 

GRAVIMETRY-WEIGHT WEIGHT ANALYSIS

 OLEUM AND ITS PERCENTAGE(%) LABBELING

VOLUME STRENGTH OF H2O2(aq) 

 PRINCIPLE OF ATOM CONSERVATION (PAOC) 

 GRAVIMETRY-WEIGHT WEIGHT ANALYSIS 

EUDIOMETRY-VOLUME VOLUME ANALYSIS OF GAS 

DEGREE OF HARDNESS OF HARD WATER 

PERCENTAGE YIELD OF CHEMICAL REACTION: 

PERCENTAGE PURITY OF GIVEN SAMPLE:

PERCENTAGE (%) AVAILABLE CHLORINE IN BLEACHING POWDER:

 

 

If 4 gm of bleaching powder dissolved to give 100 ml solution 25 ml of it react with excess of CH3COOH and KI .The Iodine liberation required 10 ml of 0.125 N Hypo solutions. Calculate % of available chlorine in the sample.

Available chlorine in sample of bleaching powder can be calculated as per the following reactions.

How many grams of Fe2O3 formed by heating of 18 gm FeO with O2.

SOLUTION:

How many moles O2 are required to needed produced 5 moles of Fe2O3.

SOLUTION:

367.5 gm KClO3 (122.5) when heated then calculate. (1) How many gram of O2 is produced? (2) How Many litre of O2 is produced at STP?

SOLUTION:

pH of a 0.1 M monobasic acid is found to be 2. Hence its osmotic pressure at a given temp. TK is:

Air contains 20℅ O2 by Volume.How many cc of air will required for oxidation of 100 cc of acetylene?

0.0833 moles of a carbohydrate having empirical formula of CH2O contains one gram hydrogen, find molecular formula

Given EF= CH2O then mass=30

And carbohydrate(CH2O) contains 1gram hydrogen:

From EF it is obvious that 2 grams hydrogen present in 30 grams then 1grams hydrogen present in 15 grams corbohydrate.

Number of moles = Given mass/M.Mass

                              0.0833  =15/M.mass

Then M.mass=180

We Must needed 

Molecular Formula(MF) = n× Empirical Formula (EF)

MF=6(CH2O) = C6H12O6

Where n = Molecular mass/Empirical mass

             n= 180/30=6

A six co-ordinate complex of formula CrCl3.6H2O has green colour. One litre of O.1M solution of the complex when treated with excess of AgNO3 gave 28.7 g of white precipitate. The formula of the complex is .... (1) [Cr(H2O)6]CI3 (2) [Cr(H2O)5CI]CI2.H2O (3) [Cr(H2O)4CI2]Cl.2H2O (4) [Cr(H2O)3Cl3].3H2O

SOLUTION: 

Given 28.7 g of white ppt obtained is 28.7/147.5= 0.2 mole Agcl precipitate Since 0.1M complexgives 0.2 mole AgCl means 2Cl− are ionisable or two Cl- ion must be present out of coordination sphere so, complex is [Cr(H2​O)5​Cl]Cl2​.H2​O