Select Board & Class
What is the bond order of N2+?
(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.
what is the law of reciprocal proportion? with examples
which element contains the greatest number of atoms?
4g he 46g na 0.40 ca 12g he
why?justify your answer?
importance of chemistry in our daily life
a sponge can be compressed,yet it is a solid.why?
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
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.
1) 1M SOLUTION OF NaNO3 HAS DENSITY 1.25 g cm-3. Calculate molality.
2) how many grams of KCLO3 MUST BE DECOMPOSED TO PREPARE 3.36 LITRES OF OXYGEN AT STP
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....
Calculate the molarity and molality of a solution made by mixing equal volumes of 30% by weight of H2SO4 (density = 1 218 g/ml) and 70% by weight of H2SO4 (density = 1 610 g/ml)
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)
WHAT IS NTP AND STP?
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?
Calculate number of atoms in 52g of Helium
calculate the volume occupied by one molecule of water?
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 equivalent weight of KMnO4 and MnO2. And explain it.
how many molecules are present in 8g of oxygen gas??
list of all the formulas necessary in this chapter (basic concepts of chemistry)?
25.4 g of iodine and 14.2 g of chlorine are made to react completely to yield a mixture of ICl and ICl3. Calculate the number of moles of ICl and ICl3 formed.
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...
what is the name of (c6h5coo)2
total no. of electron present in 18 mL of water (density of water is 1g/mL) is
What will be the equivalent weight of KMnO4 in acidic, basic and neutral medium?
what is difference between absolute mass and relative mass
what is the weight of oxygen required for the complete combustion of 2.8kg of ethylene? plz answer urgently....
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.
100 g of caco3 is treated with 500ml of M/2 solution of HCL.Find out the volume of CO2 evolved at STP.
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)
Calculate the mass of glucose required to prepare 0.1M in 500ml solution?
50.0 kg of N2 (g) and 10.0 kg of H2 (g) are mixed to produce NH3 (g). Calculate the
The first ionisation enthalpy of boron is slightly less than that if beryllium.Why??
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 ?
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?
A mixture of Na2C2O4 and KHC2O4.H2C2O4 required equal volumes of 0.1 M KMnO4 and 0.1 M NaOH separately. What is the molar ratio of Na2C2O4 and KHC2O4.H2C2O4? ( Ans : 5.5:1)
how many moles of lead (II) chloride will be formed from a reaction between 6.5g of PbO and 3.2g of HCl
The solubility product for silver chloride is 1.2 x 10-10 at 298 K.Calculate the solubility of silver chloride at 298 K.
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.
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.
An element X forms two oxides, Formula of first oxide is XO2.The first oxide contains 50% of oxygen.If the second oxide contains 60% oxygen ,the formula of the second oxide is_____
1 litre of CO2 is passed through red hot coke.The volume becomes 1.4 litres at some temperature and pressure.what will be the composition of the product?
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]
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?
calculate the number of molecules in a drop of water weighing 0.05g
calculate the no of oxygen atoms present in 4.4 g of CO2
Equivalent wt. of KMnO4 when it is converted into MnSO4 is:
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 ?
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????
Calculate the amount of water produced by 16g of Methane by combustion.
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 :-
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.
A certain compound contains carbon and oxygen. Analysis show it has 36% carbon and 64% oxygen.If its molecular weight is 400 then what is the molecular formula of the compound?
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.
Copyright © 2020 Applect Learning Systems Pvt. Ltd. All rights reserved.
E.g: 9876543210, 01112345678
We will give you a call shortly, Thank You
Office hours: 9:00 am to 9:00 pm IST (7 days a week)