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Syeda answered 1 year(s) , 10 month(s) ago

If the density of methanol is 0.793 kg/L, what is its volume needed for making 2.5 L of its 0.25M solution?

in 1 litre, mole = 0.25
in 2.5 litre, mole = 0.625

mass of 1 mole CH3OH = 32g
mass of 0.625 mole = 20g

volume = mass/density = 20/0.793 = 25.2ml

Apr 18

• 2 Likes
• 34560 Views

Apr 18

Swathi answered 3 year(s) , 10 month(s) ago

50.0 kg of N2 (g) and 10.0 kg of H2 (g) are mixed to produce NH3 (g). Calulate the NH3 (g) formed. Identify the limiting reagent in the production of NH3 in this situation.

Let us write the balanced equation

N2 + 3H2 → 2NH3

Now calculate the number of moles

Number of moles of N2 = 50 kg of N2 = 50 X

...

May 14

• 5 Likes
• 32985 Views

May 14

Swathi answered 3 year(s) , 11 month(s) ago

A solution of glucose in water is labeled as 10% w/w, what would be the molality and molarity of the solution. Density of solution is 1.2 ml-1

10%w/w solution of glucose in water means 10 g of glucose present in 100g of solution.
Therefore, Mass of glucose is 10g
Mass of water is = 100g- 10g = 90 g = 0.09 kg
And density = 1.2gmL

...

Asked by Shivam balla

May 9

• 2 Likes
• 19186 Views

Asked by Shivam balla

May 9

Syeda answered 1 year(s) , 10 month(s) ago

Number of electrons present in 1.4 grams of Nitrogen gas

Ans: Number of moles in the given weight of Nitrogen gas.
Number of moles = Given weight/molecular weight
= 1.4/28
=0.05 moles
1 mole of Nitrogen contains Avogadro number (6.023*...

Apr 18

• 4 Likes
• 19058 Views

Apr 18

Syeda answered 1 year(s) , 10 month(s) ago

Relation between molality, molarity and density

Relationship between molarity, molality and density:
Density = Molarity/Molality
Given Molarity = 12.5 mol/vol(cc)  and Molality = 11.5 mol/mass (grams)
Density = [12.5

...

Apr 20

• 0 Like
• 11312 Views

Apr 20

Jaimin answered 3 year(s) , 6 month(s) ago

50kg of nitrogen and 10kg of hydrogen are mixed to produce ammonia. Calculate the ammonia formed.

5666.6743

Apr 19

• 0 Like
• 10203 Views

Apr 19

Swathi answered 4 year(s) , 6 month(s) ago

limiting reagent

The reactant which is present in lesser amount is called limiting reagent
Limiting reagent limits the participation of other reactant which is in excess in the reaction.
Example:50 kg N 2 ...

Oct 15

• 2 Likes
• 8459 Views

Oct 15

Satyanarayana answered 4 year(s) , 11 month(s) ago

4 liters of water are added to 2 L of 6 molar HCl solutions. what is the molarity of resulting solution?

Ans: Initial Volume = 2 liters
Number of moles (n) = 6
Number of moles (n) = weight/gram molecular weight
Gram Molecular weight of HCl = 1+ 35.5 = 36.5 grams
Number of moles (n)...

May 16

• 0 Like
• 5209 Views

May 16

Swathi answered 4 year(s) , 5 month(s) ago

Number of molecules present in CO2

Molar mass of CO2 is 44g

44g of CO2  Contains 6.023X1023 molecules

200mg = 0.2 g

0.2 g of  CO2  Contains --------?

= 0.2 X6.023

...

Oct 27

• 0 Like
• 4683 Views

Oct 27

Swathi answered 3 year(s) ago

Calculate the uncertainty in the velocity of a wagon mass 3000 kg

Given data:

Mass of wagon (m) = 3000 kg

Position (Δx)= 10 pm = 10 ×10-12m = 10-11m

Planck's constant = 6.63 x10-34 Js

Βy uncertainty pr

...

Mar 26

• 1 Like
• 4621 Views

Mar 26

Satyanarayana answered 4 year(s) , 11 month(s) ago

calculate the mass percentage composition of copper pyrites ( CuFeS2 ).

Ans: Let the number of moles of given copper pyrite (CuFeS2) = 1
Every 1 mole of copper pyrite contains 2 moles of Sulphur and 1 mole of each of Copper and Iron.
Gram molecular weight of 1 mole...

May 16

• 1 Like
• 4417 Views

May 16

Swathi answered 4 year(s) , 9 month(s) ago

why the electronic configuration of actinides cannot be assigned with degree of certainity?

Due to the following reasons electronic configuration of actinides cannot be assigned with degree of certainity The difference in energy between the 5f and 6d orbitals is small for the first four elements, thor...

Jun 19

• 0 Like
• 4157 Views

Jun 19

Satyanarayana answered 4 year(s) , 6 month(s) ago

Calculation of molality

Ans: Given molarity of H2SO4 = 2.5

Density = 1.99 grm/ml

Mass solution = volume of solution*density

Let volume of solution = 100 ml

Then mass of solution = density* 100 ml

...

Sep 18

• 0 Like
• 3909 Views

Sep 18

Satyanarayana commented 4 year(s) ago

Stoichiometry

Ans: CO 2 + C = 2CO
At STP any gas occupies 22.4 liters of volume.
Therefore 22.4 litres will produce 44.8 litres of CO  (from the equation of the reaction)
...

Apr 14

• 1 Like
• 3827 Views

Apr 14

Akshita answered 4 year(s) ago

Calculate the molarity of solution of ethanol in water in which the mole fraction of ethanol is 0.040

let the moles of ethanol be n and of water be N
mole fraction = n/n+N=0.046
OR
=N/n+N=0.960
we get n/N =1/24 = mole
now using d m...

Apr 18

• 0 Like
• 3667 Views

Apr 18

Satyanarayana answered 4 year(s) , 5 month(s) ago

Colour and smell of the following salts : NaCl KBr NaBr KI CH3COONa KNO3 Na2SO4 K3PO4 Na2HPO4

Ans:

NaCl     -          White  - Odourless
KBr        -        White   - Odourless
NaBr   -           White - Odourless
KI       -             White - slight odour
CH3<

...

Asked by Rajesh joshi

Oct 21

• 0 Like
• 3273 Views

Asked by Rajesh joshi

Oct 21

Swathi answered 4 year(s) , 11 month(s) ago

Which of the following contains maximum number of oxygen atoms? a) 1.0 gm. O-atom b) 1.0 gm. O2 C) 1.0 gmO3

All contains equal number of atoms.
1 gram of oxygen atom 1 gram of oxygen molecule 1 gm of O 3 molecule contains 6.023*10 23 atoms

May 13

• 0 Like
• 3258 Views

May 13

Shamsher commented 4 year(s) ago

Zn and Hcl react Zn + 2Hcl -> ZnCl2 + H2. If 3 mole zinc is added to Hcl containing 0.52 mole of HCl. How many moles of H2 are produced?

the answer is 0.26 moles
as 2 HCL require 1 H2
and 0.52 moles of hcl gives 1/2*0.52 moles of h2
therefore we get d moles of h2 produce is 0.26
we have use the moles of hcl rather...

Apr 18

• 0 Like
• 3155 Views

Apr 18

Swathi answered 4 year(s) , 7 month(s) ago

Hydrogen sulphide (H 2 S) contains 94.11% sulphur, water (H 2 O) contains 11.11% hydrogen and sulphur dioxide (SO 2 ) contains 50% oxygen. ..

The weight of hydrogen in water = 11.11 g
The weight of oxygen  in water = 100 -11.11 = 88.89 g
weight of sulphur in sulphur dioxide = 50g
weight of oxygen sulphur dioxide  = 100 -50 = 5...

Aug 17

• 1 Like
• 2952 Views

Aug 17

Swathi answered 4 year(s) , 5 month(s) ago

Calculation of volume occupied by one atom from density and atomic mass of element

Density = mass \volume

Volume = mass/density

= 60 g/10 g/cm3 = 6 cm3

the volume occupied by 1 mole (6.023X1023 atoms) is 6 cm3

...

Oct 27

• 0 Like
• 2936 Views

Oct 27

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