Mole Concept Te...

The ratio by mass of magnesium and sulphur in magnesium sulphide is

The atomic mass of zinc is 65.37 u. Which of the following is the correct weight of 1 atom of zinc?

What is the correct number of hydrogen atoms in 0.25 mole of water?

Which of the following statements is/are correct?

(a) The word "mole" was introduced in 1896 by Wilhelm Ostwald.
(b) The mass of 1 mole of a substance is equal to its relative atomic or molecular mass in grams.
(c) The quantity of a substance can be characterised by the valency of its molecules.

Which of the following statements is/are correct?

(a) Naturally occurring oxygen is a mixture of atoms of slightly different masses called isotopes.
(b) Formula mass is used instead of molecular mass for a substance whose constituent particles are ions.
(c) Basic radicals carry negative charge.

Fluoride ion is a monovalent anion because it is a negative ion having a valency of one minus. Which of the following is also a monovalent anion?

How many moles are there in 8 g of calcium? (Atomic mass of calcium = 40 u)

Calculate the number of iron atoms in a bar of iron weighing 8 g.

(Atomic mass of iron = 56 u)

In a scientific experiment conducted in a controlled environment, 0.95 ml mixture of 'W' and 'A' was found to contain 0.57 ml of 'A' and 0.38 ml of 'W' respectively. Calculate the percentage composition of 'A' by volume.

Which of the following statements is/are false?

(a) Mole is a link between the mass of atoms and the number of atoms.
(b) The number 6.023 10²³, which represents a mole, is known as Avogadro's number.
(c) An atom represents the amount of a substance equal to its gram atomic mass.

Anurag was asked by his teacher to convert 18.066 x 10²² molecules of element X into moles. What will be the correct answer?

The mass of a single atom of an element 'A' is 3.95 x 10^-23 g. What is its atomic mass?

Element 'X' and element 'Y' combine in the ratio of 2 : 3 by mass to form 'Z'. In order to conduct an experiment, what mass of 'Y' would be required to react completely with 6 g of 'X'?

How many moles are there in 24.088 x 10²³ atoms of carbon?

How many moles are there in 28 grams of nitrogen? (Atomic mass of nitrogen = 14 u)

How many moles are there in 54 g of water (H₂O)? (Atomic masses: H = 1 u; O = 16 u)

Which of the following contains the largest number of atoms?

The number of atoms contained in 11.2 litres of SO₂ at NTP is

How many moles of CO₂ are present in 2.50 10²⁴ molecules of CO₂?

If one mole of CO and one mole of O₂ are made to react at STP, what is the total number of moles at the end of the reaction?