Atoms And Molec...

In a reaction, 32 g of sulphur reacts with a certain amount of oxygen to produce 64 g of sulphur dioxide. What is the amount of oxygen used in this reaction?

H₂O, obtained from different sources, always contains hydrogen and oxygen atoms in the respective ratio of 2 : 1. This is in accordance with which of the following?

Which among the following illustrate the law of reciprocal proportions?

Nitrogen and oxygen form three oxides.

In oxide I, 1.00 g of nitrogen combines with 0.57 g of oxygen.
In oxide II, 2.00 g of nitrogen combines with 2.24 g of oxygen.
In oxide III, 3.00 g of nitrogen combines with 5.11 g of oxygen.

These results are in accordance with which of the following?

Nitrogen and hydrogen react to form ammonia, as shown below:

N₂ (g) + 3H₂ (g) 2NH₃ (g)

The volume of hydrogen required to react completely with 10 L of N₂ and the volume of NH₃ produced, respectively, are

According to Dalton's theory, which of the following particles is indivisible and cannot be created or destroyed in a chemical reaction?

Which of the following statements contradict Dalton's atomic theory?

(A) A chemical change involves rearrangement of atoms.
(B) Atoms form ions by gain or loss of electrons.
(C) The number of atoms may change when a substance changes from solid to gaseous state.
(D) The total number of atoms during a chemical change remains unaltered.

Two elements, X and Y, have 5 and 7 valence electrons, respectively. What will be the most probable formula of the compound formed by them?

The atomic numbers of four elements - A, B, C and D - are 6, 8, 10 and 12, respectively. The two elements which can react to form an ionic bond are

The gaseous hydrocarbon acetylene, C₂H₂, used in welder's torches, releases 1300 KJ when 1 mole of C₂H₂ undergoes combustion. Which of the following statements is not true?

Mass of sodium in 62 g of Na₂O is 46 g and in 186 g of Na₂O is 138 g. This data supports the law that was given by

If a solution of glucose is 18% by mass, the number of molecules of glucose contained in 1000 g of the solution is:

Which of the following will have the same empirical and molecular formulae?

What is the mass of calcium in 250 g of calcium carbonate?
[Atomic masses of Ca, C and O respectively are 40 u, 12 u and 16 u.]

Identify the incorrect statement.

What is the number of atoms present in 112 grams of N₂?

At room temperature, the volume of a drop of water is 0.0018 ml. What is the number of water molecules present in it?

What is the molecular formula of the compound whose molecular mass is 26 u and empirical formula is CH?

How many atoms of hydrogen are present in (NH₄)₂SO₄ and NH₄H₂PO₄, respectively?

The number of aluminium ions in one formula unit of aluminium sulphate is: