tricky question from some basic concept of chemistry class 11
SINGLE CORRECT CHOICE TYPE
1) 100. have how many significant digit(s)?
2) Which of the following pair is temperature independent?
a) Molality, mole fraction
b) Molarity, mole fraction
c) Normality, molality
d) Molarity, normality
3) Which pair of species has same percentage of carbon?
a) CH3COOH, C2H5OH
b) CH3COOH, C6H12O6
c) HCOOCH3, C12H22O11
d) C6H12O6, C12H22O11
4) Two metallic oxides contain 27.6% and 30% oxygen respectively. If the formula of the first oxide is
M3O4, that of the second will be,
5) At. Wt. of X- 14 and At. Wt. of Y-16. X and Y combine to form a new substance Z. if 4 moles of Y
combine with two mole of X to give one mole of Z, the mass of one mole of Z will be,
MULTIPLE CORRECT CHOICE TYPES
1. The atomic weight of two elements A and B are 20 and 40 respectively. Which of the following statement(s) is / are correct for these two elements?
a) x g of A contains y atoms which is equal to atoms present in x g of B.
b) x g o A contains y atoms which is equal to atoms present in 2x g of B.
c) at STP, x L of monatomic gas A is equal to x L of monatomic gas B.
d) at STP, x L of monatomic gas A weighs y g and y L of monatomic gas B is measured x L.
2. Which of the following is/are equivalent to 32g of a substance?
a) One mole of sulphur molecules.
b) One mole of oxygen atom
c) One gram-atom of sulphur.
d) 22.4 L of O2 gas at STP.
3. The true value of a result is 2.00g. A student X take 2 measurements and report the results as 2.01g
and 1.99g as results. These 2 values are –
c) precise but not accurate
d) accurate but not precise
4. The following substances are present in different containers
i) 1 g-atom of nitrogen
ii) 1 mole of calcium
iii) 1 mole of silver
iv) 1 mole of oxygen molecule
v) 1023 atoms of carbon
vi) 1g of Fe
The correct order of increasing masses (in g) is/are:
a) iii < vi < i < v
b) iii < vi < iv < ii
c) vi < v < i < iv
d) iii < ii < v < iv
5. 1 meter is equal to-
a) 3.2808 ft
b) 1.0936 yards
c) 0.000621 mile
d) 104 mm
ASSERTION & REASON TYPE (
For the following question, choose the correct answer from the codes a, b, c, d defined as follows
a) St I is true, St II is true and II is correct explanation of I
b) St I is true. St II is true and II is not the correct explanation of I
c) St I is true and St II is False
d) St I is false and St II is True.
e) St I and St II are both false.
1. I: molality of the solution depends on temperature.
II: with the increase in temperature volume of the solution increases.
2. I: Molecular mass = 2 x V.D.
II: V.D. is the mass ratio of 1 mole of vapour to that of hydrogen.
3. I: Eq. Wt. of H3PO2 is equal to its molecular mass
II: H3PO2 is a monobasic acid
4. I: Empirical and molecular formula of Na2C03 is same.
II: Na2CO3 does not form hydrate.
5. I: 22 carat gold is a compound.
II: Steam is a mixture.
LINKED COMPREHENSION TYPE
The earlier method for determining the molecular weight of protein was based on the chemical analysis. The following compositions of proteins were found:
Hemoglobin: 0.335% Fe
Cytochrome protein: 0.376% Fe
Peroxidase enzyme: 0.29% Se
1. if hemoglobin contains 4 atoms of iron, then approximate molecular mass of hemoglobin is:
2. the mole% of Se in the enzyme Peroxidase is
3. if the Cytochrome protein contains one atom per molecule then the molecular mass of protein
4. how many atoms of Se are present in 1 microgram of Peroxidase enzyme assuming one
molecule of enzyme contains 1 atom of Se:
5. how many moles of iron are present in 1 mg of hemoglobin
MATRIX MATCH TYPE
1. COLUMN 1 COLUMN 2
Concentration terms factors affecting concentration
a) Molarity p) temperature
b) Molality q) pressure
c) Mole fraction r) dilution
d) Normality s) volume
2. COLUMN 1 COLUMN 2
a) Avogadro’s law p) equivalent weight
b) Laws of reciprocal proportion q) molecular weight
c) Gay Lussac’s law r) molar volume
d) Tritimetry s) vapour density
3. COLUMN 1 COLUMN 2
a) 1 L p) 10-5 N
b) 1 J q) 0.289 cal
c) 9.9x106 erg r) 10-3 m3
d) 1 dyne s) 6.25x1018 eV
4. COLUMN 1 COLUMN 2
a) Force p) J
b) Energy q) 1/s
c) Frequency r) kg m2 s-1
d) Work s) kg ms-2
INTEGER TYPE QUESTION
1. How many significant digits are present in the result of the following calculation:
(0.02856 x 298.15 x 0.112)/0.5785
2. 250 ml of ‘x’ M solution and 500 ml of ‘y’ M solution of a solute A are mixed and diluted to 2 L to produce a final concentration of 1.6 M. If x: y=5: 4, calculate (x + y) upto one significant figure.
3. The order of magnitude of the molarity of the excess acid left in a solution formed by mixing 10 ml of decimolar KOH solution with 200ml of centimolar H2SO4 solution is ‘X’. Find | X |.
4. The reaction, N2 (g) + H2 (g) à 2NH3 (g) is carried out by taking 56g of nitrogen and 64g of hydrogen. Find out the total number of moles of ammonia formed after the reaction at 1 atm and 00C.
5. The empirical formula of an inorganic salt is of the form NaxSyOz which have the following % composition: Na = 29.11%, S = 40.51% and O = 30.38%. Calculate the value of (x + y + z).