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  • 1 answers

Gaurav Seth 6 hours ago

Limiting Reagent

  • In a chemical reaction, reactant which is present in the lesser amount gets consumed after sometime and after that no further reaction takes place whatever be the amount of the other reactant present. Hence, the reactant which gets consumed, limits the amount of product formed and is, therefore, called the limiting reagent.


50.0 kg of N(g) and 10.0 kg of H2 (g) are mixed to produce NH3 (g).

Calculate the NH3 (g) formed. Identify the limiting reagent in the production of NH3 in this situation.

  • 5 answers

Heena Bilam 4 hours ago

Dinesh publications

Naveen Kumar Das 10 hours ago

ABC Of Chemistry by Modern publication
Ncert is best... Then you go for other books
S. L. Arora
  • 2 answers

Jasmeen Kaur 1 day, 1 hour ago

It is a branch of science that deals with composition, structure and properties of matter and the changes in which the matter undergoes under different conditions.....

Anjali Yadav 1 day, 3 hours ago

It is the branch of science
  • 1 answers

Kinshuk Shukla 1 day, 23 hours ago

Avogadro constant means 6.023×10^23per mole . Means that it's dimension is per mole
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  • 4 answers

Naveen Kumar Das 10 hours ago

Dharam Das Bhoyar 1 day, 19 hours ago

Ice floats on water because it's density is lesser than water

Jasmeen Kaur 2 days, 2 hours ago

Ice floats on water because of the anomalous expansion of water after 4°C........ HOPE IT HELPS......

Yogita Ingle 2 days, 22 hours ago

In the solid state (ice), intermolecular interactions lead to a highly ordered but loose structure in which each oxygen atom is surrounded by 4 hydrogen atoms; two of these hydrogen atoms are covalently bonded to the oxygen atom, and the two others (at longer distances) are hydrogen bonded to the oxygen atom’s unshared electron pairs.

this open structure of ice causes its density to be less than that of the liquid state, in which the ordered structure is partially broken down and the water molecules are (on average) closer together. When water freezes, a variety of structures are possible depending on the conditions. 9 different forms of ice are known and can be interchanged by varying external pressure and temperature.

  • 5 answers

Linthoingambi Ningthoujam 2 days, 20 hours ago


Vaishali Sahu 2 days, 20 hours ago


Vaishali Sahu 2 days, 20 hours ago

32.4% OK

Bhusan Lal Sahu 2 days, 21 hours ago

32.4% I am vaishali

Gaurav Seth 2 days, 23 hours ago

The molecular formula of sodium sulphate is (Na2SO4).

Molar mass = atomic mass of Na(23) + atomic mass of S(32.066) + atomic mass of O(16)

Molar mass of (Na2SO4) = [(2 × 23.0) + (32.066) + 4 (16.00)] = 142.066 

Mass percent of an element 


∴ Mass percent of sodium: 

  • 2 answers

Anjali Yadav 1 day, 3 hours ago


Monika Gautam 2 days, 23 hours ago

  • 1 answers

Monika Gautam 2 days, 23 hours ago

3g of H2 and 17g of NH 3
  • 1 answers

Vinay Kumar Maurya 3 days, 9 hours ago

Ammonium nitrate does not burn on its own. Instead, it acts as a source of oxygen that can accelerate the combustion (burning) of other materials. For combustion to occur, oxygen must be present.
  • 2 answers

Aman Kumar 4 days, 2 hours ago

A protic acid

Yogita Ingle 4 days, 2 hours ago

When a protic acid (HX) is added to an asymmetric alkene, the acidic hydrogen attaches itself to the carbon having a greater number of hydrogen substituents whereas the halide group attaches itself to the carbon atom which has a greater number of alkyl substituents.
It is important to note that the Markovnikov’s rule was developed specifically for its application in the addition reaction of hydrogen halides to alkenes.

  • 3 answers

Anjali Yadav 1 day, 3 hours ago

mol dm-3

Gaurav Seth 4 days, 8 hours ago


In chemistry, the most commonly used unit for molarity is the number of moles per litre, having the unit symbol mol/L or mol⋅dm3 in SI unit. A solution with a concentration of 1 mol/L is said to be 1 molar, commonly designated as 1 M.

Yogita Ingle 4 days, 8 hours ago

Molarity is the number of moles of a substance per liter of solution, also known as molar concentration. A capital M signifies solutions labeled with molar concentration.

SI units molarity : mol dm-3.

  • 3 answers
Thank you

Sonami Barik 4 days, 8 hours ago

Lewis suggested that a chemical bond involved sharing of electrons.He described what he called the cubical atom,because a cube has 8corners , to represent the outer valence shell electrons which can be shared to create a bond . This is his octet rule

Yogita Ingle 4 days, 8 hours ago

The representation of molecules in Lewis electron dot structure or just a Lewis structure is in honor of the American chemist Gilbert Newton Lewis.

Lewis dot structures also called electron dot structures are diagrams that describe the chemical bonding between atoms in a molecule. They also display the total number of lone pairs present in each of the atoms that constitute the molecule. Lewis dot structures are commonly referred to as electron dot structures or Lewis structures. Lewis defined a base as an electron pair donor and an acid as an electron pair acceptor.

  • 1 answers

Yogita Ingle 4 days, 8 hours ago



Refers to mass of a mole of a substance

Refers to the mass of molecules

Also known as molecular weight

It determines the mass of single molecule

SI unit is g/mol to use in higher calculations

Measured in amu

It is defined as the mass of Avogadro number of atoms/molecules or compounds

No particular melting point

Measurement given to compounds, atoms or molecules

Determined only in molecules

Less accurate than molecular mass

Accurate to use in higher calculations

Example: Mass of 1 mole of oxygen is 15.9994 grams. Therefore the molar mass = 15.9994 g/mol


Molecular mass of Ca(OH)2 = 74 atomic mass units

  • 1 answers

Yogita Ingle 4 days, 20 hours ago

They are set of 4 numbers, which give complete information about the address of electron.

There are 4 types of quantum numbers:

  • Principal quantum number.
  • Azimuthal quantum number.
  • Magnetic quantum number.
  • Spin quantum number.
  • 1 answers

Yogita Ingle 5 days, 5 hours ago

A mole is defined as the mass of the substance which consists of the equal quantity of basic units. Example atoms in 12 grams are the same as 12C. The basic units can be molecules, atoms or formula units based on the substance. A mole fraction indicates the number of chemical elements. One mole of any substance is equal to the value of 6.023 x 1023 (Avagadro number). It can be used to measure the products obtained from the chemical reaction. The unit is denoted by mol.

The formula for the number of moles formula is expressed as
Number of Moles = mass of substance/, the mass of one mole

Example 1: Determine the number of moles in 95g of MnO2.



Mass of MnO2 = 95g

Mass of one mole MnO2 = 86.94g

Number of moles formula is

Number of moles = Mass of substance / Mass of one mole

Number of moles = 95 / 86.94

Number of moles = 1.092 mol


  • 1 answers

Gaurav Seth 5 days, 7 hours ago

Moles of methanol present in 2.5 L of 0.25 M solution




Moles of CH3OH = 2.5 * 0.25 = 0.625


Mass of CH3OH = 0.625 * 32 = 20 g


(∵ Molecular mass of CH3OH = 12 + 1 * 3 + 16 + 1 = 32)


0.793 *  g of CH3OH is present in 1000 mL


20 g of CH3OH is present in



  • 2 answers

Dev Kumar 4 days, 2 hours ago


Vaibhav Chaudhary 5 days, 18 hours ago

A mole of a substance or a mole of particles is defined as exactly 6.02214076×1023 particles, which may be atoms, molecules, ions, or electrons. In short, for particles 1 mol = 6.02214076×1023.
  • 0 answers
  • 2 answers

Siya Sharma 5 days, 20 hours ago

Isotopes are atoms with same atomic number but different atomic mass (12/6C,13/6C.14/6C)

Yogita Ingle 6 days, 2 hours ago

The term “isotope” mainly refers to the variation in the atomic mass or weight of an element.
It is also defined as variants of a particular element where these variants will have the same number of protons but differ in the number of neutrons in the atom.

When we look at carbon it also has three isotopes namely Carbon-12, Carbon-13, and Carbon-14. The numbers 12, 13, and 14 are the isotopes’ atomic masses. Here, Carbon-12 is a stable isotope whereas carbon-14 is mostly a radioactive isotope.

  • 2 answers
Thanks yogita ingle

Yogita Ingle 6 days, 3 hours ago

Scientific notation is a form of presenting very large numbers or very small numbers in a simpler form. As we know, the whole numbers can be extended till infinity, but we cannot write such huge numbers in a piece of paper. Also, the numbers which are present at the millions place after the decimal needed to be represented in a simpler form. Thus, it is difficult to represent a few numbers in their expanded form. Hence, we use scientific notations.

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