Some Basic Conc...

Molarity of liquid water at 4°C is

Which of the following statements about pure substances is correct ?

In scientific notation for numbers, any number can be represented in the form, N × 10n   where,

The prefix of the fraction 10^–12 and its symbol respectively are

Matter can be classified at the macroscopic or bulk level as

Significant figures are

On reduction with hydrogen, 3.6 g of an oxide of a metal left 3.2 g of the metal. If the vapour density of the metal was 32 g/L, then the simplest formula of the oxide would be 

Chemistry does not play a major role in

If 6.3 g of NaHCO₃ is added to 15.0 g of CH₃COOH solution, the weight of the residue is found to be 18.0 g. What is the mass of CO₂ released in the reaction?

One micrometer stands for

The volume of oxygen necessary for complete combustion of 20 litres of propane is _________ litres.

The approximate number of molecules in one litre of water is 

Consider the following skeleton equation:

__As₂O₃ + __SnCl₂ + __HCl → __SnCl₄ + __As + __H₂O

What are the stoichiometric coefficients of As₂O₃, SnCl₂, HCl, SnCl₄, As and H₂O, when the above equation is balanced?

The ratio between the volumes of the gaseous reactant and the gaseous products can be expressed in simple whole numbers. This law is known as

How many significant figures are present in 0.324?

If 500 cc of water gas (CO + H₂) is exploded with 500 cc of oxygen, then what will be the volume ratio of CO₂ : Steam : O₂?
(Assume that the volumes are measured under the same temperature and pressure.)

If in a reaction, HNO₃ is reduced to NO, the mass of HNO₃ absorbing one mole of electrons would be

Directions: The following question has four choices, out of which ONLY ONE is correct.

A certain non-metal X forms two oxides A and B. The mass percentage of oxygen in oxide A (X₄O₆) is 43.7%, which is the same as that of X in the oxide B. The formula of the oxide B is

Which of the following correctly represents a balanced chemical equation?

The molarity of concentrated sulphuric acid ( = 1.834 g cm^–3) containing 95% of H₂SO₄ by mass is

In a homogeneous mixture,the components are

SI units for Base Physical Quantities of length, mass and current are

NH₃ obtained from different sources always contains nitrogen and hydrogen in the ratio 1 : 3. This is in accordance with

Particles of compounds are

The mass of 2.6 moles of sulphur dioxide is

Atomic mass of carbon is 12 u. One atom of magnesium is twice as heavy as one carbon atom. What is the atomic mass of magnesium?

Fill up the  blank  with  suitable word in the statement,

" Physical properties are those properties which are measured or observed--------------- changing the identity or the composition of the substance ."

Which among the following illustrates the law of reciprocal proportions?

Volume of CO₂ obtained from complete decomposition of 126 g of CaCO₃ at STP is

Precision and Accuracy refer to _______ of various measurements for the same quantity repeatedly  and agreement of a particular value to the ------- --------  of the result , respectively.