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What is the bond order of N2+?
what is the law of reciprocal proportion? with examples
importance of chemistry in our daily life
a sponge can be compressed,yet it is a solid.why?
concentrated aqueous sulphuric acid is 98% H2SO4 (sulphuric acid ) by mass and has a density of 1.80gL-1 (gL raise to the power -1) . Volume of acid required to make one litre of 0.1 M H2SO4 is???
Two oxides of a metal contain 27.6% and 30% oxygen, respectively. If the formula of the first compound is M3O4, find the formula of the second compound.
The no. of moles of KMnO4 that will be needed to react completely with one mole of ferrous oxalate in acidic solution is
(a) 3/5 (b)2/5
(c)4/5 (d)None of these
explain MOLARITY, MOLALITY and NORMALITY in DETAIL.?
what is the relation between mole fraction and molality?
please can anyone explain it in a simple way....
Difference between homogeneous and heterogeneous mixture.
what is the effect of temperature on molarity over molality?
Find the molarity and molality of a 15% solution of H2SO4 ( density=1.020 g/cm3 and atomic mass = H=1, O=16, S=32amu)
1 g of Mg is burnt in a closed vessel which contains 0.5 g of dioxygen. what is the limiting reagent? What is the amount of Mgo formed in the reaction?
WHAT IS NTP AND STP?
Calculate number of atoms in 52g of Helium
calculate the volume occupied by one molecule of water?
Calculate the equivalent weight of KMnO4 and MnO2. And explain it.
list of all the formulas necessary in this chapter (basic concepts of chemistry)?
1. If the density of methanol is 0.793 kg L-1, what is the volume needed for making 2.5 L of its 0.25 M solution ?
Please answer in brief with explanation to it...
total no. of electron present in 18 mL of water (density of water is 1g/mL) is
what is difference between absolute mass and relative mass
Commercially available concentrated Hcl contains 38% Hcl by mass. (1) what is the molarity of the solution ( density of solution =1.19 g mL -1)
(2) What volume of concentrated Hcl is required is required to make 1.0 L of an 0.10 M Hcl.
The normality of 10% (weight/volume) acetic acid is:-
the total no. of valence electrons in 4.2g of N3- ion is ??in terms of Na(Na is the avogadro no._)
find the number of atoms of each type present in 3.42grams of cane sugar ( C12H22O11)
1.determine the percentage composition of a mixture of anhydrous sodium carbonate and sodium bicarbonate from the following data:
wt of mixture taken = 2g , loss in weight on heating = 0.11g
2.how many grams of 90% pure Na2so4 can be produced from 250 gm of 95% pure Nacl?
50.0 kg of N2 (g) and 10.0 kg of H2 (g) are mixed to produce NH3 (g). Calculate the
What's the difference between molarity and molality?
Calculate the weight of iron which will be converted into its oxide ( Fe3O4) by the action of 14.4g of steam on it ?
the vapour density of a mixture containing NO2 and N2O4 is 38.3 at 27 degree celsius. calculate the mole of NO2 in 100 molemixture.
how many moles of lead (II) chloride will be formed from a reaction between 6.5g of PbO and 3.2g of HCl
3g of H2 react with 29g of O2 to yield H2O .
(1) Which is limiting raegent?
(2) Calculate the maximum amount of H20 that can be formed?
(3) Calculate the amount of one of the reactants which remains unreacted.
What will be the equivalent weight of KMnO4 in acidic, basic and neutral medium?
Q1. Calculate the number of atoms in
a) 0.5 mole atoms of nitrogen
b) 0.2 mole moleules of nitrogen
c) 3.2g of sulphur
d)3.4 g of H2S
Q2. how many molecules of water of hydration are present in 252 mg of oxalic acid?
What is the relation between molality, molarity and density? is this correct, 'molality = molarity / density'? I got this off the internet....
molarity = mole / volume density = mass / volume molality = mole / mass molality = molarity / density mole / mass = (mole / vol) / (mass / vol) mole / mass = mole / mass [proved]
calculate the number of molecules in a drop of water weighing 0.05g
What is the number of moles of KMnO4 that will be needed to react with one mole of sulphite ion in acidic solution?
calculate the no of oxygen atoms present in 4.4 g of CO2
the % of Se in peroxidase anhydrous enzyme is 0.5% by weight(atomic weight=78.4).then what is the minimum molecular weight of peroxidase anhydrous enzyme ?
Calculate the amount of water produced by 16g of Methane by combustion.
Q. A compound contains 4.07% hydrogen, 24.27% carbon and 71.65% chlorine. Its molar mass is 98.96gm. What are its empirical and molecular formula????
Assuming fully decomposed, the volume of CO2 released at STP on heating 9.85 g of BaCO3?
a metal oxide contains 60% metal.the equivalent weight of metal is :-
A)12
B)60
C)40
D)24
Give reasons.
(i) Neither q nor w is a state function but q+w is a state function.
(ii) The dissolution of Ammonium chloride in water is endothermic, but still it dissolves in water.
(iii) The entropy of steam is more than that of water at its boiling point.
please check if the answers for the following questions are correct :)
1) This is determined by looking at the ratio of the stoichiometric coefficients of CO to CO2, which is 3:3.2) Looking at the equation, the ratio of the number of moles of H2 that reacts to that of HCl that forms is 1:2. Thus, the number of moles of H2 that were used= 1/2(number of moles of HCl that were formed)= 1/2(12.0)= 6.0 moles3) 1.00 mole of H2O= 6.02x10^23 H2O molecules5.00 moles of H2O= 5x6.02x10^23 H2O molecules= 3.01x10^24 H2O moleculesAn H2O molecule contains 3 atoms. Thus, the number of atoms in 3.01x10^24 H2O molecules= 3x3.01x10^24= 9.03x10^24 atoms4) 1 mole of a gas occupies 22.4L at STPThus, the volume occupied by 78.0 moles of a gas at STP= (78.0x22.4)L= 1747.2L= 1747L(answer correct to 3 significant figures)5) 22.4L of a gas contains 1 mole of a gas at STPThus, the number of moles contained by 11.2L of a gas at STP= 11.2/22.4= 0.5 moles6) Since Fe is in excess, O2 is the limiting reagent, implying that all of it reacts.The ratio of the number of moles of O2 that reacts to that of Fe2O3 that forms is 3:2.Thus, the number of moles of Fe2O3 that form= 2/3(number of moles of O2 that reacts)= 2/3(6.00)= 4.00 moles7) Relative Atomic Mass(RAM) of Mg= 2424.0g= 1 mole of Mg48.6g= 48.6/24.0= 2.025 moles of MgRelative Formula Mass(RFM) of HCl= (RAM of H)+(RAM of Cl)= 1.0+35.5= 36.536.5g= 1 mole of HCl150g= 150/36.5= 4.110 moles of HClAccording to the equation, the ratio of the number of moles of Mg required to that of HCl required is 1:2. Since there is less Mg than required, Mg is the limiting reagent.8) 24.0g= 1 mole of Mg24.3g= 24.3/24.0= 1.0125 moles of Mg36.5g= 1 mole of HCl75.0g= 75.0/36.5= 2.0548 moles of HClAgain, the ratio of the number of moles of Mg required to that of HCl required is 1:2. Since there is more HCl than required, Mg is the limiting reagent, implying that all of it reacts.The ratio of the number of moles of Mg that reacts to that of MgCl2 that forms is 1:1. Therefore, the number of moles of MgCl2 that forms= the number of moles of Mg that reacts= 1.0125Relative Formula Mass(RFM) of MgCl2= (RAM of Mg)+2(RAM of Cl)= 24+2(35.5)= 951 mole of MgCl2= 95.0g1.0125 moles of MgCl2= 95.0x1.0125= 96.1875g9) False. It is actually the number of moles of each reactant that must be compared.10) Relative Atomic Mass of Hg= 200.6200.6g= 1 mole of Hg503.0g= 503.0/200.6= 2.51 moles of HgThe expected number of moles of O2 produced= 1/2(3.00)= 1.50Percent yield= (actual yield/theoretical yield)x100%= (1.25/1.50)x100%= 83.3%Relative Molecular Mass(RMM) of N2= 2(RAM of N)= 2(14)= 2828.0g= 1 mole of N284.0g= 84.0/28.0= 3 moles of N2Relative Molecular Mass(RMM) of NH3= (RAM of N)+3(RAM of H)= 14+3(1)= 1717.0g= 1 mole of NH385.0g= 85.0/17.0= 5.00 moles of NH3The expected ratio of the number of moles of N2 that reacts to that of NH3 that forms is 1:2. Thus, the percent yield= (actual amount of NH3/expected amount of NH3)x100%= (5/6)x100%= 83.3%12) Relative Molecular Mass(RMM) of SO2= (RAM of S)+2(RAM of O)= 32+2(16)= 6464.00g= 1 mole of SO264.06g= 64.06/64.00= 1.0009 moles of SO2RMM of SO3= 32+3(16)= 8080.0g= 1 mole of SO375.0g= 75/80= 0.93750 moles of SO3The expected ratio of the number of moles of SO2 that reacts to that of SO3 that forms is 1:1. Thus, percent yield= (0.93750/1.0009)x100%= 93.68%13) False. The theoretical yield can actually be calculated before the experiment has commenced by determining the the expected ratio of the number of moles of the limiting reagent to that of the product.14) True.
Calculate the amount of carbon dioxide that could be produced when
(i) 1 mole of carbon is burnt in air.
(ii) 1 mole of carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
2.76 g of silver carbonate (at. mass of Ag = 108 ) on being heated strongly yields a residue weighing ?
Number of atoms in 4.25 g of NH3is approximatly............
derive the ideal gas equation pv = nRT from gas laws.
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Syllabus
What is the bond order of N2+?
what is the law of reciprocal proportion? with examples
importance of chemistry in our daily life
a sponge can be compressed,yet it is a solid.why?
concentrated aqueous sulphuric acid is 98% H2SO4 (sulphuric acid ) by mass and has a density of 1.80gL-1 (gL raise to the power -1) . Volume of acid required to make one litre of 0.1 M H2SO4 is???
Two oxides of a metal contain 27.6% and 30% oxygen, respectively. If the formula of the first compound is M3O4, find the formula of the second compound.
The no. of moles of KMnO4 that will be needed to react completely with one mole of ferrous oxalate in acidic solution is
(a) 3/5 (b)2/5
(c)4/5 (d)None of these
explain MOLARITY, MOLALITY and NORMALITY in DETAIL.?
what is the relation between mole fraction and molality?
please can anyone explain it in a simple way....
Difference between homogeneous and heterogeneous mixture.
what is the effect of temperature on molarity over molality?
Find the molarity and molality of a 15% solution of H2SO4 ( density=1.020 g/cm3 and atomic mass = H=1, O=16, S=32amu)
1 g of Mg is burnt in a closed vessel which contains 0.5 g of dioxygen. what is the limiting reagent? What is the amount of Mgo formed in the reaction?
WHAT IS NTP AND STP?
Calculate number of atoms in 52g of Helium
calculate the volume occupied by one molecule of water?
Calculate the equivalent weight of KMnO4 and MnO2. And explain it.
list of all the formulas necessary in this chapter (basic concepts of chemistry)?
1. If the density of methanol is 0.793 kg L-1, what is the volume needed for making 2.5 L of its 0.25 M solution ?
Please answer in brief with explanation to it...
total no. of electron present in 18 mL of water (density of water is 1g/mL) is
what is difference between absolute mass and relative mass
Commercially available concentrated Hcl contains 38% Hcl by mass. (1) what is the molarity of the solution ( density of solution =1.19 g mL -1)
(2) What volume of concentrated Hcl is required is required to make 1.0 L of an 0.10 M Hcl.
The normality of 10% (weight/volume) acetic acid is:-
the total no. of valence electrons in 4.2g of N3- ion is ??in terms of Na(Na is the avogadro no._)
find the number of atoms of each type present in 3.42grams of cane sugar ( C12H22O11)
1.determine the percentage composition of a mixture of anhydrous sodium carbonate and sodium bicarbonate from the following data:
wt of mixture taken = 2g , loss in weight on heating = 0.11g
2.how many grams of 90% pure Na2so4 can be produced from 250 gm of 95% pure Nacl?
50.0 kg of N2 (g) and 10.0 kg of H2 (g) are mixed to produce NH3 (g). Calculate the
What's the difference between molarity and molality?
Calculate the weight of iron which will be converted into its oxide ( Fe3O4) by the action of 14.4g of steam on it ?
the vapour density of a mixture containing NO2 and N2O4 is 38.3 at 27 degree celsius. calculate the mole of NO2 in 100 molemixture.
how many moles of lead (II) chloride will be formed from a reaction between 6.5g of PbO and 3.2g of HCl
3g of H2 react with 29g of O2 to yield H2O .
(1) Which is limiting raegent?
(2) Calculate the maximum amount of H20 that can be formed?
(3) Calculate the amount of one of the reactants which remains unreacted.
What will be the equivalent weight of KMnO4 in acidic, basic and neutral medium?
Q1. Calculate the number of atoms in
a) 0.5 mole atoms of nitrogen
b) 0.2 mole moleules of nitrogen
c) 3.2g of sulphur
d)3.4 g of H2S
Q2. how many molecules of water of hydration are present in 252 mg of oxalic acid?
What is the relation between molality, molarity and density? is this correct, 'molality = molarity / density'? I got this off the internet....
molarity = mole / volume
density = mass / volume
molality = mole / mass
molality = molarity / density
mole / mass = (mole / vol) / (mass / vol)
mole / mass = mole / mass [proved]
calculate the number of molecules in a drop of water weighing 0.05g
What is the number of moles of KMnO4 that will be needed to react with one mole of sulphite ion in acidic solution?
calculate the no of oxygen atoms present in 4.4 g of CO2
the % of Se in peroxidase anhydrous enzyme is 0.5% by weight(atomic weight=78.4).then what is the minimum molecular weight of peroxidase anhydrous enzyme ?
Calculate the amount of water produced by 16g of Methane by combustion.
Q. A compound contains 4.07% hydrogen, 24.27% carbon and 71.65% chlorine. Its molar mass is 98.96gm. What are its empirical and molecular formula????
Assuming fully decomposed, the volume of CO2 released at STP on heating 9.85 g of BaCO3?
a metal oxide contains 60% metal.the equivalent weight of metal is :-
A)12
B)60
C)40
D)24
Give reasons.
(i) Neither q nor w is a state function but q+w is a state function.
(ii) The dissolution of Ammonium chloride in water is endothermic, but still it dissolves in water.
(iii) The entropy of steam is more than that of water at its boiling point.
please check if the answers for the following questions are correct :)
answers
1) This is determined by looking at the ratio of the stoichiometric coefficients of CO to CO2, which is 3:3.2) Looking at the equation, the ratio of the number of moles of H2 that reacts to that of HCl that forms is 1:2. Thus, the number of moles of H2 that were used= 1/2(number of moles of HCl that were formed)= 1/2(12.0)= 6.0 moles3) 1.00 mole of H2O= 6.02x10^23 H2O molecules5.00 moles of H2O= 5x6.02x10^23 H2O molecules= 3.01x10^24 H2O moleculesAn H2O molecule contains 3 atoms. Thus, the number of atoms in 3.01x10^24 H2O molecules= 3x3.01x10^24= 9.03x10^24 atoms4) 1 mole of a gas occupies 22.4L at STPThus, the volume occupied by 78.0 moles of a gas at STP= (78.0x22.4)L= 1747.2L= 1747L(answer correct to 3 significant figures)5) 22.4L of a gas contains 1 mole of a gas at STPThus, the number of moles contained by 11.2L of a gas at STP= 11.2/22.4= 0.5 moles6) Since Fe is in excess, O2 is the limiting reagent, implying that all of it reacts.The ratio of the number of moles of O2 that reacts to that of Fe2O3 that forms is 3:2.Thus, the number of moles of Fe2O3 that form= 2/3(number of moles of O2 that reacts)= 2/3(6.00)= 4.00 moles7) Relative Atomic Mass(RAM) of Mg= 2424.0g= 1 mole of Mg48.6g= 48.6/24.0= 2.025 moles of MgRelative Formula Mass(RFM) of HCl= (RAM of H)+(RAM of Cl)= 1.0+35.5= 36.536.5g= 1 mole of HCl150g= 150/36.5= 4.110 moles of HClAccording to the equation, the ratio of the number of moles of Mg required to that of HCl required is 1:2. Since there is less Mg than required, Mg is the limiting reagent.8) 24.0g= 1 mole of Mg24.3g= 24.3/24.0= 1.0125 moles of Mg36.5g= 1 mole of HCl75.0g= 75.0/36.5= 2.0548 moles of HClAgain, the ratio of the number of moles of Mg required to that of HCl required is 1:2. Since there is more HCl than required, Mg is the limiting reagent, implying that all of it reacts.The ratio of the number of moles of Mg that reacts to that of MgCl2 that forms is 1:1. Therefore, the number of moles of MgCl2 that forms= the number of moles of Mg that reacts= 1.0125Relative Formula Mass(RFM) of MgCl2= (RAM of Mg)+2(RAM of Cl)= 24+2(35.5)= 951 mole of MgCl2= 95.0g1.0125 moles of MgCl2= 95.0x1.0125= 96.1875g9) False. It is actually the number of moles of each reactant that must be compared.10) Relative Atomic Mass of Hg= 200.6200.6g= 1 mole of Hg503.0g= 503.0/200.6= 2.51 moles of HgThe expected number of moles of O2 produced= 1/2(3.00)= 1.50Percent yield= (actual yield/theoretical yield)x100%= (1.25/1.50)x100%= 83.3%Relative Molecular Mass(RMM) of N2= 2(RAM of N)= 2(14)= 2828.0g= 1 mole of N284.0g= 84.0/28.0= 3 moles of N2Relative Molecular Mass(RMM) of NH3= (RAM of N)+3(RAM of H)= 14+3(1)= 1717.0g= 1 mole of NH385.0g= 85.0/17.0= 5.00 moles of NH3The expected ratio of the number of moles of N2 that reacts to that of NH3 that forms is 1:2. Thus, the percent yield= (actual amount of NH3/expected amount of NH3)x100%= (5/6)x100%= 83.3%12) Relative Molecular Mass(RMM) of SO2= (RAM of S)+2(RAM of O)= 32+2(16)= 6464.00g= 1 mole of SO264.06g= 64.06/64.00= 1.0009 moles of SO2RMM of SO3= 32+3(16)= 8080.0g= 1 mole of SO375.0g= 75/80= 0.93750 moles of SO3The expected ratio of the number of moles of SO2 that reacts to that of SO3 that forms is 1:1. Thus, percent yield= (0.93750/1.0009)x100%= 93.68%13) False. The theoretical yield can actually be calculated before the experiment has commenced by determining the the expected ratio of the number of moles of the limiting reagent to that of the product.14) True.
Calculate the amount of carbon dioxide that could be produced when
(i) 1 mole of carbon is burnt in air.
(ii) 1 mole of carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
2.76 g of silver carbonate (at. mass of Ag = 108 ) on being heated strongly yields a residue weighing ?
Number of atoms in 4.25 g of NH3is approximatly............
derive the ideal gas equation pv = nRT from gas laws.