Mole Concept

3g of carbon react completely with 5g of oxygen leaving no reactants. Find the mole fraction of carbon monoxide in the product gases.

• 0.75g

• 0.2g

• 2g

• 10g

A compound contains 25% hydrogen and 75% carbon by mass. Determine the empirical formula of the compound.

• C₂H₂

• CH₄

• C₂H₄

• C₂H₆

A gaseous alkane is exploded with oxygen. The moles of O₂ for complete combustion and CO2 formed is in the ratio 7:4. Deduce molecular formula of the alkane.

• C2H6

• C2H2

• C3H4

• C3H6

One atom of an element 'X' weighs 6.664 * 10^-23 gm. The number of gram atoms in 40kg of it is -

• 9975

• 99.7

• 997.5

• 155.2

If from 3 moles MgSO₄.7H₂O, all the 'O' atoms are taken out and converted into ozone find the number of O₃ molecules formed.

• 16

• 5

• 10

• 11

The following process has been used to obtain iodine from oil-field brines in California.

How many grams of AgNO₃ are required in the first step for every 254 kg I₂ produced in the third step.

• 140kg

• 210kg

• 230kg

• 340kg

Equal weight of Zn metal and iodine are mixed together and the iodine is completely converted to ZnI2. What fraction of weight of the original Zinc remains unreacted. (At. wt. Zn = 65).

• 0.744

• 0.9

• 1.1

• 0.98

What weight of CaCO3 must be decomposed to produce the sufficient quantity of carbon dioxide to convert 21.2kg of Na2CO3 completely in to NaHCO3. (A.M Na = 23, Ca = 40)

• 200kg

• 2kg

• 20kg

• 10kg

Find the molarity of Cl- ion in solution which is obtained by mixing one mole each of BaCl2,NaCl AND HCl in 500ml water.

• 5

• 4

• 7

• 8

What volume of water should be added to 50ml of HNO₃ having density 1.5 g ml^-1 and 63.0% by weight to have one molar solution.

• 800ml

• 400ml

• 700ml

• 1000ml