Some Basic Conc...

Which of these concentration units is temperature-dependent?

An empirical formula represents the simplest

The calculation of masses or, (sometimes volumes also) of the reactants and the products involved in a chemical reaction is called

The prefix giga is used for the multiple

A given compound always contains exactly the same proportion of elements by weight. This law is stated by

0.2M NaOH means

The simplest formula of a compound which contains 85.6% C and 14.4% H by mass is

One mole is the amount of a substance that contains as many particles or entities as there are atoms in

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

Two containers P and Q of equal volume (1 litre each) contain 6 g of O₂ and SO₂, respectively, at 300 K and 1 atm. Which of the following statements is correct?

The prefix atto is used for the fraction

If 112 ml of NH₃ gas at STP is passed through 100 ml of 0.1 N H₂SO₄, the amount of solid NaOH required to make the solution neutral is

What is the number of carbon atoms present in 329 amu of tear gas (CCl₃NO₂)?

0.9 g of a compound of mol. wt. 90 and containing only C, H and O is exploded with 224 ml of oxygen. After cooling, the volume was 560 ml, and on passing through KOH solution, the remaining volume is 112 ml. If all volumes were measured at STP, the molecular formula of the liquid compound is

Which of the following relations is correct?

What is the approximate number of molecules in 4.25 g of NH₃?

A 2.0 g mixture of Na₂CO₃ and NaHCO₃ suffered a loss of 0.12 g on heating. The percentage of Na₂CO₃ in the mixture was

Density of water at room temperature is 1.0 gml^-1. How many molecules are there in one drop of water if its volume is 0.05 ml?

If haemoglobin (molecular weight 16.7 kda (kilodalton)) contains 0.335% Fe (atomic weight 56), what is the number of iron atoms per molecule of haemoglobin?

A sample of 9 ml of a gaseous organic compound on combustion with exactly sufficient amount of oxygen produces 4 ml of CO₂, 6 ml of steam and 2 ml of nitrogen. If the organic compound contains only C, H and N, then its molecular formula is

An insecticide contains 47.5% C, 2.54% H and 50% Cl by mass. Its empirical formula is

Avogadro's constant is the number of entities ( viz. atoms , molecules or ions  ) present in -------------  mole of a substance.

Molarity is defined as,

Two isotopes of an element X are ¹⁴X and ¹⁵X. If the average atomic mass of X is 14.0067 u, what are the respective percentage abundances of ¹⁴X and ¹⁵X?

Molecular formula represents

The number of oxygen atoms in 4.4 g of carbon dioxide is

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

According to the law of conservation of mass, a balanced chemical equation

If in a given reaction,  is reduced to , the mass of  absorbing one mole of electrons would be

A sample of hard water contains 40 mg of Ca²⁺ ions per litre. The amount of washing soda (Na₂CO₃) required to soften five litres of the sample would be 

The number of moles of solute present in 1 kg of solvent is called--------------.