Some Basic Concepts of Chemistry · Chemistry · NEET

The amount of glucose required to prepare $$250 \mathrm{~mL}$$ of $$\frac{\mathrm{M}}{20}$$ aqueous solution is : (Molar mass of glucose : $$180 \math...

$$1.0 \mathrm{~g}$$ of $$\mathrm{H}_2$$ has same number of molecules as in:

On complete combustion, 0.3 g of an organic compound gave 0.2 g of CO$$_2$$ and 0.1 g of H$$_2$$O. The percentage composition of carbon and hydrogen i...

1 gram of sodium hydroxide was treated with $$25 \mathrm{~mL}$$ of $$0.75 \mathrm{~M} \mathrm{~HCl}$$ solution, the mass of sodium hydroxide left unre...

The highest number of helium atoms is in

A compound X contains $$32 \%$$ of A, $$20 \%$$ of B and remaining percentage of C. Then, the empirical formula of $$\mathrm{X}$$ is : (Given atomic m...

The density of 1 M solution of a compound 'X' is 1.25 g mL$$^{-1}$$. The correct option for the molality of solution is (Molar mass of compound X = 85...

The right option for the mass of $$\mathrm{CO}_{2}$$ produced by heating $$20 \mathrm{~g}$$ of $$20 \%$$ pure limestone is (Atomic mass of $$\mathrm{C...

The density of the solution is 2.15 g mL$$-$$1, then mass of 2.5 mL solution in correct significant figures is :

What fraction of Fe exists as Fe(III) in Fe0.96O ? (Consider Fe0.96O to be made up of Fe(II) and Fe(III) only)

In one molal solution that contains 0.5 mole of a solute, there is

What mass of 95% pure CaCO3 will be required to neutralise 50 mL of 0.5 M HCl solution according to the following reaction? CaCO3(s) + 2HCl(aq) $$\to$...

An organic compound contains 78% (by wt.) carbon and remaining percentage of hydrogen. The right option for the empirical formula of this compound is ...

Which one of the following has maximum number of atoms?

The number of protons, neutrons and electrons in 17571Lu, respectively, are :

The number of moles of hydrogen molecules required to produce 20 moles of ammonia through Haber’s process is :

A mixture of 2.3 g formic acid and 4.5 g oxalic acid is treated with conc. H2SO4 . The evolved gaseous mixture is passed through KOH pellets. Weight (...

In which case is number of molecules of water maximum?

Which of the following is dependent on temperature?

Suppose the elements X and Y combine to form two compounds XY2 and X3Y2. When 0.1 mole of XY2 weights 10 g and 0.05 mole of X3Y2 weighs 9 g, the atomi...

What is the mass of the precipitate formed when 50 mL of 16.9% solution of AgNO3 is mixed with 50 mL of 5.8% NaCl solution ? (Ag = 107.8, N = 14, O =...

What is the mole fraction of the solute in a 1.00 m aqueous solution?

The number of water molecules is maximum in

If Avogadro number NA, is changed from 6.022 $$ \times $$ 1023 mol$$-$$1 to 6.022 $$ \times $$ 1020 mol$$-$$1, this would change...

A mixture of gases contains H2 and O2 gases in the ratio of 1 : 4 (w/w). What is the molar ratio of the two gases in the mixture ? ...

1.0 g of magnesium is burnt with 0.56 g O2 in a closed vessel, Which reactant is left in excess and how much ? (At. wt. Mg = 24, O = 16)

When 22.4 liters of H2(g) is mixed with 11.2 litres of Cl2(g), each at S.T.P. the moles of HCl(g) formed is equal to ...

Equal masses of H2, O2 and methane have been taken in a container of volume V at temperature 27oC in identical conditions. The ratio of the volumes of...

In an experiment it showed that 10 mL of 0.05 M solution of chloride required 10 mL of 0.1 M solution of AgNO3, which of the following will be the for...

6.02 $$ \times $$ 1020 molecules of urea present in 100 mL of its solution. The concentration of solution is

How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0 M HNO3? The concentrated acid is 70% HNO3....

Which has the maximum number of molecules among the following ?

25.3 g of sodium carbonate, Na2CO3 is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentr...

The number of atoms in 0.1 mol of a triatomic gas is (NA = 6.02 $$ \times $$ 1023 mol$$-$$1)

10 g of hydrogen and 64 g of oxygen were filled in a steel vessel and exploded. Amount of water produced in this reaction will be

What volume of oxygen gas (O2) measuread at 0oC and 1 atm, is needed to burn completely 1 L of propane gas (C3H8) measured under the same conditions ...

An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empirical formula of the compound wo...

How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g HCl ?

Concentrated aqueous sulphuric acid is 98% H2SO4 by mass and has a density of 1.80 g mL$$-$$1. Volume of acid required to make one litre of 0.1 M H2SO...

An element, X has the following isotopic composition: 200X : 90%  199X : 8.0%  202X : 2.0% The weighted average atomic mass of th...

The mole fraction of the solute in one molal aqueous solution is

The maximum number of molecules is present in

2.5 litre of 1 M NaOH solution is mixed with another 3 litre of 0.5 M NaOH solution. Then find out molarity of resultant solution.

The percentage of C, H and N in an organic compound are 40%, 13.3% and 46.7% respectively then empirical formula is

Which has maximum molecules?

Specific volume of cylinfrical virus particle is 6.02 $$ \times $$ 10$$-$$2 cc/g whose radius and length are 7 $$\mathop A\limits^ \circ $$ and 10 $$...

Molarity of liquid HCl, if density of solution is 1.17 g/ce is

Percentage of Se in peroxidase anhydrous enzyme is 0.5% by weight (at. wt. = 78.4) then minimum molecular weight of peroxide anhydrous enzyme is

Oxidation numbers of A, B, C are + 2, +5 and $$-$$2 respectively. Possible formula of compound is

Volume of CO2 obtained by the complete decomposition of 9.85 g of BaCO3 is