Calculate the molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).
Mole fraction of C2H5OH= .................1
Let the moles of C2H5OH= X
Now density of water = 1 (given)
And the weight of 1000ml of water = volume * density (from density = mass/volume)
= 1000 x 1=1000g
Therefore moles of water = 1000/18= 55.55 mol (18g is molecular mass of water)
Also mole fraction of C2H5OH= 0.040 (given)
Putting the values in equation 1,we get
=0.040=X/X+55.55
=0.040X+2.222 = X
OR X= 2.3145 mol
Molarity of solution = 2.314 M
Calculate the amount of carbon dioxide that could be produced when
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(ii) 1 mole of carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
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(i) 300 atoms of A + 200 molecules of B
(ii) 2 mol A + 3 mol B
(iii) 100 atoms of A + 100 molecules of B
(iv) 5 mol A + 2.5 mol B
(v) 2.5 mol A + 5 mol B
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(iii) 1 g Li (s)
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How many grams of HCl react with 5.0 g of manganese dioxide?
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(i) Express this in percent by mass.
(ii) Determine the molality of chloroform in the water sample.
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(iii) molecular formula.
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(ii) 208
(iii) 5005
(iv) 126,000
(v) 500.0
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(ii) CH3CH=CH2,
(iii) (CH3)2CO,
(iv) CH2=CHCN,
(v) C6H6
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Assign oxidation number to the underlined elements in each of the following species:
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(b) NaHSO4
(c) H4P2O7
(d) K2MnO4
(e) CaO2
(f) NaBH4
(g) H2S2O7
(h) KAl(SO4)2.12 H2O
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(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.
A liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
a) What is the initial effect of the change on vapour pressure?
b) How do rates of evaporation and condensation change initially?
c) What happens when equilibrium is restored finally and what will be the final vapour pressure?
Justify the position of hydrogen in the periodic table on the basis of its electronic configuration.
Equilibrium constant, Kc for the reaction
N2 (g) + 3H2 (g) ↔ 2NH3 (g) at 500 K is 0.061
At a particular time, the analysis shows that composition of the reaction mixture is 3.0 mol L–1 N2, 2.0 mol L–1 H2 and 0.5 mol L–1 NH3.
Is the reaction at equilibrium?
If not in which direction does the reaction tend to proceed to reach equilibrium?
Define the bond length.
Assign the position of the element having outer electronic configuration
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CH4 (g) + H2O (g) ↔ CO (g) + 3H2 (g)
(a) Write as expression for Kp for the above reaction.
(b) How will the values of Kp and composition of equilibrium mixture be affected by
(i) increasing the pressure
(ii) increasing the temperature
(iii) using a catalyst ?
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(iii) p - nitrotoluene
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Calculate the the molarity solution of methanol in 1 litre offer water in which of the mole fraction of is 0.5
In this question water density given but still need to solve this question not have density of solution so a/c to my opinion that question fandamentically wrong. And if think water density is equal to solution density than answers will be2.01M
2.22/1.040=2.14461~2.1 Therefore,Molarity of Ethanol= 2.1M
WTF! 2.22÷1.040 = 2.134615~2.1M
write answer is 2.22
Volume of water i.e 1 litre is converted to 1000ml
Volume of water i.e 1 litre is converted to 1000ml
Why vol of water 1000 why God why
the answer is totally wrong,it should be 2.09 M
Thanks