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551.

Which of the following represents 1 g-molecule of the substance?A. `6*02xx10^(24)` molecules of `NH_(3)`B. 4 g of heliumC. 40 g of CaOD. 127 g of iodine.

Answer» Correct Answer - B
He is known as monoatomic molecule.
552.

One atom of an element weighs `1*8xx10^(-22)` g its atomic mass isA. `29*9`B. `18`C. `108*36`D. `154`

Answer» Correct Answer - C
Mass of 1 atom `= 1*8xx10^(-22) g`
Mass of `6*02xx10^(23)` atoms
`= 6*02xx10^(23)xx1*8xx10^(-22)g`
`= 6*02xx1*8xx10g = 108*36g`
`:.` Atomic mass of element `= 108*36`.
553.

The number of neutrons in `1*8` g of water will approximately beA. `4*216xx10^(23)`B. `8*432x10^(23)`C. `4*816xx10^(23)`D. `4*216xx10^(24)`

Answer» Correct Answer - C
`H_(2)O = 2_(1)^(1)H+._(8)^(16)O`
`:.` neutrons, `._(0)^(1)n = 0+8`
`.^(2)H_(2)O = (1*8)/(18) = 0*1`
Hence `._(0)^(1)n = 8xx0*1xx6*02xx10^(23)`
`=4*816xx10^(23)`
554.

The mass of 1 mole of neutrons `(m_(n) = 1.675 xx 10^(-27)` kg) is:A. `1.800xx10^(-3)` kgB. `1.008xx10^(-4)` kgC. `1.080xx10^(-3)` kgD. `1.008xx10^(-3)` kg

Answer» Correct Answer - D
Mass of 1 mole
`=1.675xx10^(-27)xx6.02xx10^(23) kg=1.008xx10^(-3)` kg.
555.

Which has maximum number of atomsA. 24 gms of `C_((12))`B. 56 gms of `Fe_((56))`C. 27 gms of `Al_((27))`D. 108 gms of `Ag_((108))`

Answer» Correct Answer - A
12 g. of carbon `=6.023xx10^(23)`
24 g. of Carbon `=(6.023xx10^(23))/12 xx24=12.046xx10^(23)`
But 56 gm, 27 gm. And and 108 gm of Fe, Al the Ag respectively contains same no. (Avogardos number) of atoms.
556.

Assertion (A): A reaction between `Fe` and `I_(2)` occurs, but a reaction between `Fe^(2+)` and `I^(ө)` does not occur. Reason (R ): `Fe` is a better reducing agent than `I^(ө)`.A. Statement 1 is true, statement 2 is true, statement 2 is a correct explanation for statement 6B. Statement 1 is true, statement 2 is true, statement 2 is not a correct explanation for statement 6C. Statement 1 is true, statement 2 is falseD. Statement 1 is false, statement 2 is true

Answer» Correct Answer - A
Both (1) and (2) are correct and (2) Is the correct explanatio for (1).
`I_(2)+Fe rarr Fe^(2+)+2 I^(ɵ)`
`I^(ɵ)+Fe^(2+) rarr` No reaction
The oxidation potential of `Fe//Fe^(2+)` is greater than the oxidation potential of `2I//I_(2)^(ɵ)`.
557.

No reaction occurs in which of the following equationsA. `I^(ɵ)+Fe^(2+) rarr`B. `F_(2)+2NaCl rarr`C. `Cl_(2) +2NaF rarr`D. `I_(2)+2NaBr rarr`

Answer» Correct Answer - A::C::D
Reduction potential of `F_(2) gt Cl_(2) gt Br_(2) gt I_(2)`. So `F_(2)` can displace `Cl^(Θ), Br^(Θ) and I^(Θ)` but not vice versa. Similarly, `Cl_(2)` can displace `Br^(Θ) and I^(Θ)` but not vice versa and `Br_(2)` can displace only `I^(Θ)` but not vice versa. In (a) `Fe(" not " Fe^(2+))` is a better reducing agent tahn `I^(Θ)`.
558.

Which of the following is`//`are disproportionation redox changes?A. `(NH_(4))_(2) Cr_(2)O_(7) rarr N_(2)+Cr_(2)O_(3)+4 H_(2)O`B. `5H_(2)O_(2)+2 ClO_(2)+2 overset(ɵ)(OH) rarr 2 Cl +overset(ɵ)(%)O_(2)+6H_(2)O`C. `3 ClO^(ɵ) rarr ClO_(3)^(ɵ)+Cl^(ɵ)`D. `2HCuCl_(2) overset("Dilution")underset("with water")(rarr) Cu+Cu^(2+)+4Cl+.^(ɵ)2H^(o+)`

Answer» Correct Answer - C::D
(c) `2e^(-) + ClO^(Θ) rarr Cl^(Θ)` (Reduction)
`x -2 = -1 " " x = -1`
`x = +1`
`ClO^(Θ) rarr ClO_(3)^(Θ) + 4e^(-)` (Oxidation)
`x = 1 " " x = 5`
(d) In `HCuCl_(2), Cu` is in +1 oxidation state which disproportionates to `Cu^(2+) and Cu^(0)`
559.

Which of the following reactions does not involve oxidation-reduction ?A. `2 Rb+2 H_(2)O rarr 2 RbOH+H_(2)`B. `2 CuI_(2) rarr 2 CuI=I_(2)`C. `NH_(4)Cl +NaOH rarr NaCl +NH_(3)+H_(2)O`D. `4 KCN+Fe(CN)_(2) rarr K_(4)[Fe(CN)_(6)]`

Answer» Correct Answer - C::D
In both (c) and (d), the oxidation numbers of the various elements in the molecule do not change.
560.

In acidic medium dichromate oin osxidizes stannous ion as : `xSn^(2+)+yCr_(2)O_(7)^(2-)+zH^(+) to aSn^(4+)+bCr^(3+)cH_(2)O`A. The value of `x : y` is `1 : 3`B. The value of `x+y+z` is 18C. The value of `a : b` is `3 : 2`D. The value of `z-c` is 7

Answer» Correct Answer - B::C::D
`3 Sn^(2+) +14 H^(+) + Cr_(2)O_(7)^(2-) rarr 3 Sn^(3+) + 2Cr^(3+) +7H_(2)O`.
561.

A hydrocarbon contain 86% carbon, 488 ml of the hydrocarbon weight 1.68 g at STP. Then the hydrocarbon is anA. (a)AlkaneB. (b)AlkeneC. (c )AlkyneD. (d)Arene

Answer» Correct Answer - B
`{:("Element","At. wt".,"Mole","Ratio","Empirical formula"),(C=86%,12,7.1,1,CH_(2)),(H=14%,1,14,2,"Belongs to alkene" C_(n)H_(2n)):}`
562.

Definig 1 amu as `1//12` of the mass of a `._(6)^(12)C` atom means that protons and neutrons each have a mass of almost exactly 1 amu, becauseA. atin as a whole is electrically neutralB. `C` atom contains equal number of protons and neutronsC. the mass of an electron is negligibel compared with the mass of proton and neutronD. neutrons are slightly heavier than protons

Answer» Correct Answer - C
`m_(p) = 1.007276, m_(n) = 1.008665, m_(e) = 5.485799xx10^(-4)`
563.

What is the % of `H_(2)O` in `Fe(CNS)_(3).3H_(2)O`?A. (a)45B. (b)30C. (c )19D. (d)25

Answer» Correct Answer - C
In Fe `(CNS)_(3).3H_(2)O`
`%` of `H_(2)O=(3xx18)/284xx100=19%`.
564.

The number of Na atom in 46 g Na (Atomic weight of Na = 23 ) isA. `6.023xx10^(23)`B. 2C. 1D. `12.046xx10^(23)`

Answer» Correct Answer - D
`because ` 23 g of Na contains `= 6.023xx 10^(23)` atoms
`therefore` 1 g of contains ` = (6.023 xx 10^(23))/23 `atoms
`therefore` 46 g of Na contains `= (6.023 xx 10^(23)/23) xx 46` atoms
`=12-046 xx 10^(23)` atoms
565.

Complete combustion of 0.858 g of compound X gives 2.63 g of `CO_(2)` and 1.28 g of` H_(2)`O. The lowest molecular mass X can haveA. (a)43 gB. (b)86 gC. (c )129 gD. (d)172 g

Answer» Correct Answer - A
`%C=12/44xxW_(CO_(2))/Wxx100=12/44xx2.63/0.858xx100=83.6%`
`%H=2/18xxW_(H_(2)O)/Wxx100= =2/18xx1.28/.858xx100=16.4%`
`{:(,%(a),At.wt.(b),a//b,Ratio),(C,83.6,12,6.96,1),(H,16.4,1,16.4,2.3):}`
`C_(3)H_(7)=12xx3+7=43 g`.
566.

In an experiment it is shown that `10 mL` of `0.05 M` solution of chloride required `10 mL` of `0.1 M` solution of `AgNO_(3)`, which of the following will be the formula of the chloride (X stands for the symbol of the element other than chlorine):A. (a)`X_(2)Cl`B. (b)`X_(2)Cl_(2)`C. (c )`XCl_(2)`D. (d)`XCl_(4)`

Answer» Correct Answer - c
Millimoles of solution of chloride`=0.05xx10=0.5`
Millimoles of `AgVO_(3)` solution `=10xx0.1=1`
So, the millimoles of `AgNO_(3)` are double than the chloride solution.
`:. XCl_(2)+2AgNO_(3) rarr 2AgCl+X(NO_(3))_(2)`
567.

If `2.73g` of oxide of vanadium contains `1.53g` fo the metal vanadium, the empirical formula of the oxide isA. `V_(2) O_(5)`B. `V_(2) O_(3)`C. `V_(3) O_(4)`D. `V O_(2)`

Answer» Correct Answer - A
`n_(V) = (1.53g)/(51g mol^(-1)) = 0.03, n_(O) = (1.20g)/(16g mol^(-1)) = 0.075`
`(n_(V))/(n_(O)) = (0.03)/(0.075) = (30)/(75) = (2xx15)/(5xx15) = 2:5`
`:. EF` is `V_(2) O_(5)`.
568.

`6.02xx10^(20)` molecules of urea are present in `100 mL` solution. The concentration of urea solution is:A. `0.1 M`B. `0.001 M`C. `0.1 M`D. `0.02 M`

Answer» Correct Answer - A
Number of moles (urea)
`= (6.02xx10^(20) "molecules")/(6.02xx10^(23) "molecules" mol^(-1))`
`= 0.01 mol`
Volume of soltuion in liters `= (100 mL)/(1000 mL L^(-1)) = 0.1L`
Molarity `= ("Number of moles")/("Volume in liters") = (0.01 mol)/(0.1) = 0.01M`
569.

`6.02xx10^(20)` molecules of urea are present in `100 mL` solution. The concentration of urea solution is:A. (a)`0.01 M`B. (b)`0.001 M`C. (c )`0.1 M`D. (d)`0.02 M`

Answer» Correct Answer - a
`6.02xx10^(23)` molecules is 1 mole
`6.02xx10^(20)` molecules is `10^(-3)` mole
`100 mL` has `10^(-3)` mole
`1000 mL` has `(10^(-3))/100xx1000=10^(-2)`
570.

The empirical formula fo a compound is `CH_(2)O`. Its vapor density is `30`. It reacts with sodium metal. The compound isA. `HCOOCH_(3)`B. `CH_(2)O`C. `CH_(3)CH_(2) COOH`D. `CH_(3)COOH`

Answer» Correct Answer - D
`MF = n xx EF`
`n = ("Molecular mass")/(EFM) = (2 xx "Vapor density")/(EFM), n = 2`
`:. MF = C_(2) H_(4) O_(2)`
Since the compound contains acidic `H` atom, it is acetic acid,.
`CH_(3) COOH + Na rarr (1)/(2) H_(2) + CH_(3) COONa`
571.

`6.02xx10^(20)` molecules of urea are present in `100 mL` solution. The concentration of urea solution is:A. (a)0.1 MB. (b)0.01 MC. (c )0.02 MD. (d)0.001 M

Answer» Correct Answer - B
`M=("Moles of urea")/("V in litre")`
`=(6.02xx10^(20)xx1000)/(6.023xx10^(23)xx100)=10^(-2) M`
572.

x g of Ag was dissolved in `HNO_(3)` and the solution was precipitated. The value of x isA. `1*08 g`B. `2*16 g`C. `2*70 g`D. `1*62 g`

Answer» Correct Answer - B
`143.5 g` AgCl contains Ag = 108 g
`2*87` g AgCl contains Ag `= (108xx2*87)/(143*5) = 2*16 g`
573.

Standard molar volume of all gases isA. `22.4 L`B. `22.4 m^(3)`C. `22.4 ml`D. `22.4 cm^(3)`

Answer» Correct Answer - A
Volume occupied by 1 mol of ideal gas under standard conditions is `22.4 L`
574.

Which of the following has the minimum mass?A. `6.02xx10^(22)H_(2)` moleculesB. `1120 c c` of `CO_(2)` at `STP`C. `0.1` mol of `NH_(3)`D. `0.1g` atom of carbon

Answer» Correct Answer - A
(1) `n_(H_(2)) = (6.02xx10^(22))/(6.02xx10^(23)) = 0.1` mol
`:. M_(H_(2)) = (0.1 mol) (2g mol^(-1)) = 0.2g`
(2) `n_(CO_(2))=(1120 c c)/(22400c c"mol"^(-1))=0.05"mol"`
`:. M_(CO_(2)) = (0.05 "mol") (44g "mol"^(-1)) = 2.2g`
(3) `m_(NH_(3)) = (0.1 "mol") (17g "mol"^(-1)) = 1.7g`
(4) `0.1g` atom of `C = 0.1` mol
`= (0.1 "mol") (12 g "mol"^(-1)) = 1.25`
575.

When 400 g of a `20%` solution by weight was cooled, 50 g of solute precipitated. What is the percentage by mass of solute in the remaining solution ?A. `8.57%`B. `15%`C. `12.25%`D. `9.5%`

Answer» Correct Answer - A
576.

Normality of 2 M sulphuric acid isA. (a)2 NB. (b)4 NC. (c )`N/2`D. (d)`N/4`

Answer» Correct Answer - B
`H_(2)PO_(4)` is dibasic `N=2 M=2xx2=4`.
577.

The solution of sulphuric acid contains 80% by weight `H_(2)SO_(4)`. Specific gravity of this solution is 1.71. Its normality is aboutA. (a)18.0B. (b)27.9C. (c )1.0D. (d)10.0

Answer» Correct Answer - B
`N=(10xxsp. "Gr. Of the solution" xx" wt". % "of solute"xx"Mol. Wt".)/("Molecular wt. of solute"xx"Eq. Wt".)`
`N=(10xx1.71xx80xx98)/(98xx49)=27.9`
578.

Which of the following solution has normality equal to molarity ?A. `H_(2) SO_(4)` aqueous solutionB. `H_(3) PO_(4)` aqueous solutionC. `HNO_(3)` aqueous solutionD. `Mg (OH)_(2)` aqueous solution

Answer» Correct Answer - C
579.

Normality of `2`M sulphuric acid isA. (a)`2 N`B. (b)`4N`C. (c )`N/2`D. (d)`N/4`

Answer» Correct Answer - a
`H_(2)SO_(4)` is dibasic `N=2M=2xx2=4`
580.

The set of numerical coefficients that balances the chemical equation `K_(2)CrO_(4)+HCltoK_(2)Cr_(2)O_(7)+KCl+H_(2)O`A. `1,1,2,2,1`B. `2,2,1,1,1`C. `2,1,1,2,1`D. `2,2,1,2,1`

Answer» Correct Answer - D
The balanced equation is
`2K_(2)CrO_(4)+2HCl to K_(2)Cr_(2)O_(7)+2KCl+H_(2)O`
581.

The numerical value of N/n (where N is the number of molecules in a give sample of gas and n is the number of moles of gas) isA. `8.314`B. `6.02xx10^(23)`C. `0.0821`D. `1.66xx10^(-19)`

Answer» We know,
`6.02xx10^(23)` molecules (N) = 1 mole (n)
`:. (N)/(c) = (1)/(6.02xx10^(23))=1.62xx10^(-24)`
582.

The mass of 11.2 L of ammonia gas at S.T.P. isA. `8.5 g`B. `85 g`C. `17 g`D. `1.7 g`

Answer» Correct Answer - A
Molar mass of `NH_(3)=14+3xx1=17g mol^(-1)`
`:.` Mass of 22.4 L of `NH_(3)` at S.T.P. = 17 g
`:.` Mass of 11.2 L of `NH_(3)` at S.T.P. = 8.5 g
583.

The same amount of a metal combines with 0.20 g of oxygen and with 3.17 g of a halogen. Hence equivalent mass of halogen isA. 127 gB. 80 gC. `36.5` gD. 9 g

Answer» Correct Answer - A
`0.20` g oxygen `equiv 3.17` g halogen
`therefore` Equivalent mass of halogen `equiv (3.17)/0.20 xx 8 = 126.8` g
`~=127` g
584.

The same amount of a metal combines with 0.20 g of oxygen and with 3.17 g of a halogen. Hence equivalent mass of halogen isA. `127 g`B. `80 g`C. `35.5 g`D. `9 g`

Answer» Correct Answer - A
0.20 g of oxygen = 3.17 g of halogen
8 g of oxygen `= (3.17)/(0.20)xx8`g of halogen
`= 126.8g`
`:.` Eq. mass of halogen `=126.8~~127`
585.

0.1 g of metal combines with 46.6 mL of oxygen at STP. The equivalent weight of metal isA. 12B. 24C. 18D. 36

Answer» a) 1 mole of `O_(2)` = 4 equivalent of oxygen
22400 mL of `O_(2)` = 4 equivalent of oxygen
46.6 mL of `O_(2)` = (4/22400) xx 46.6 = 0.00832 eq.
Equivalent of metal = Equivalent of oxygen
(Weight)/(Equivalent) = 0.00832
0.1/E = 0.00832 `rARr` E= (0.1)/(0.00832) = 12.0
586.

The sulphate of a metal `M` contains `9.87%` of `M`, This sulphate is isomorphous with `ZnSO_(4).7H_(2)O`. The atomic weight of `M` isA. `40.3`B. `36.3`C. `24.3`D. `11.3`

Answer» Correct Answer - C
As the given sulphate is isomorphous with `ZnSO_(4).7H_(2)O` its formula would be `MSO_(4).7H_(2)O`m is the atomic weight of M, molecular weight of `mSO_(4).7H_(2)O = m + 32 + 64 + 126 m + 222`
Hence % of M `= (m)/(m + 222) xx 100 = 9.87` (given) or 100m `= 9.87 m + 222 xx 9.87 or 90.13m = 222 xx 9.87`
or `m = (222 xx 9.87)/(90.13) = 24.3`
587.

The sulphate of a metal A contains 20% of M. This sulphate is isomorphous with `ZnSO_(4).7H_(2)O`. The atomic mass of M isA. `12`B. `24`C. `36`D. `48`

Answer» Correct Answer - B
`("Mass of metal sulphate")/("Mass of metal")`
`("Eq. mass of M + Eq. mass of" `SO_(4)^(2-)`)/("Eq. mass of M")`
`(100)/(20)=(E+48)/(E)`
`5E =E+48`
`4E=48` or `E=12`
As metal sulphate is isomosphous with `ZnSO_(4).7H_(2)O`
Valency of M = Valency of Zn =2
Hence At. mass of M = Eq. mass `xx` valency
`=12xx2=24`
588.

Express `-20^(@)C` in kelvin scale.

Answer» Correct Answer - 253.15 K
589.

Express 900.00 in scientific notation.

Answer» Correct Answer - `9xx10^(2)`
590.

On heating `100g` of `Na_(2)SO_(4) 10 H_(2) O` will loose ..... % of water.A. `44.1`B. `65.3`C. `55.9`D. `34.7`

Answer» Correct Answer - C
It is equal to the mass precent of wate.
Percent water
`= ("Mass of" H_(2) O "in 1 mol of compound")/("Molar mass of compound") xx 100%`
`= (180)/(320) xx 100% = 59.9%`
591.

At `100^(@)C` and `1 atm`, if the density of the liquid water is `1.0 g cm^(-3)` and that of water vapour is `0.0006 g cm^(-3)`, then the volume occupied by water molecules in `1 L` of steam at this temperature isA. (a)`6 cm^(3)`B. (b)`60 cm^(3)`C. (c )`0.6 cm^(3)`D. (d)`0.06 cm^(3)`

Answer» Correct Answer - D
For water vapour, `P=0.0006 g c c^(-1)`
`:. 0.0006="Mass"/"Volume"="Mass"/1000`
Mass`=1000xx0.0006=0.6` g`:. 0.0006="Mass"/"Volume"="Mass"/1000`
Mass`=1000xx0.0006=0.6` g
the density of liquid water is `1 g c c^(-1)`
So, the volume occupied by water is
`"Mass"/"Density"=0.6/1=0.6 c c`
592.

The modern atomic weight scale is based onA. `C^(12)`B. `O^(16)`C. `H^(1)`D. `C^(13)`

Answer» Correct Answer - A
The modern atomic weight scale is based on `C^(12)`
593.

Express the following in the scientific notation: a. `0.0048` b. `234000` c. `8008` d. `500.0` e. `6.0012`

Answer» Correct Answer - `(i) 4.8 xx 10^(-3) `
`(ii) 2.34 xx10^(5)`
(iii) `8.008xx 10^(3)`
(iv) `5.000xx10^(2)`
`(v) 6.0012`
`(i) 0.0048=4.8 xx10^(-3)`
`(ii) 234,000=2.34xx10^(5)`
`(iii) 8008=8.008 xx10^(3)`
(iv) `500.0=5.000xx10^(2)`
(v) `6.0012=6.0012`
594.

A resucing agent is a substance which canA. Accept electronB. Donate electronsC. Accept protonsD. Donate protons

Answer» Correct Answer - B
A substance which is capable of reducing other substances and is capable of donating electrons during reduction is called agent or reductant.
595.

Which one is oxidising substance?A. `C_(2)H_(2)O_(2)`B. `CO`C. `H_(2)S`D. `CO_(2)`

Answer» Correct Answer - D
`CO_(2)` is an oxidizing agent.
596.

A divalent metal has 12 equivalent weight. The molecular weight of its oxide isA. 16B. 32C. 40D. 52

Answer» Correct Answer - C
Equivalent weight of metal = 12
Equivalent weight of oxygen = 8
Equivalent weight of MO (oxide) with divalent metal
= 20
Thus, molecular weight of metal oxide = 40
597.

The equivalent mass of chlorine is 35.5, and the molar mass of copper is 63.5. The equivalent mass of copper chloride is 99.0. Hence, formula of copper chloride isA. `CuCl`B. `Cu_(2)Cl`C. `CuCl_(2)`D. None of these

Answer» Correct Answer - A
Eq. mass of copper chloride = 99
Eq. mass of chlorine = 35.5
`:.` Eq. mass of copper = 99-35.5 = 63.5
`:.` Valency of copper `= ("At mass of copper")/("Eq. mass of copper") = 1`
`:.` Formula of copper chloride is `CuCl`
598.

In the combustion of 5.00 g of a metal, 9.44 g of metal oxide are formed. Hence, equivalent mass of the metal isA. `4.44` gB. `9.00` gC. `5.00` gD. `2.22` g

Answer» Correct Answer - B
Matel `= 5. 00` g
Metal oxide ` = 9. 44` g
Oxygen combined `= 4. 44` g
`4.44` g of oxyen combined with `= 5. 00` g metal
`therefore 8 ` g oxygen combined with `= 5.00/4.44 xx 8` g metal
`=9.00` g
599.

Arsenic forms two oxides, one of which contains 65.2 % and the other 75.7% of the element. Hence, equivalent masses of arsenic are in the ratioA. `1:2`B. `3:5`C. `13:15`D. `2:1`

Answer» Correct Answer - B
In first oxide
Mass of arsenic = 65.2
Mass of oxygen = 34.8
`:.` Eq. mass of arsenic `= (65.2)/(34.8)xx8 = 14.99`
In second oxide,
Mass of arsenic = 75.7 g
Mass of oxygen = 24.3 g
`:.` Eq. mass of arsenic `= (75.7)/(24.3)xx8`
`=24.92`
`underset(("oxide I"))("Eq. mass of arsenic")" : "underset(("oxide II"))("Eq. mass of arsenic")`
`14.99:24.92`
or 3:5
600.

Red colored compound , hemoglobin present in blood contains `0.355% Fe (AM = 56u)` If four atoms of `Fe` are present per molucule of hemoglobin, its molecular mass would beA. `63098 u`B. `78654 u`C. `54786 u`D. `98036 u`

Answer» Correct Answer - A
As there are 4 atoms of `Fe` per molecule, we have
`% Fe = (4 xx AM of Fe)/("MM of hemoglobin") xx 100%`
(`AM` is atomic mass, `MM` is molar mass)
`0.335% = (4 (56u))/(MM) xx 100%`
`:. MM = (4(56u))/(0.335%) xx 100% = 63098 u`