RC Mukherjee Test: Mass & Stoichiometry - NEET MCQ

2NaN₃ → 2Na + 3N₂
As above reaction is already balanced we can write:
2 moles of NaN₃ ≡ 3 moles of N₂ 
So, moles of NaN₃ ≡ 8.75 moles of N₂
8.75 x 2/3 = 5.83 moles of NaN₃. 

C H₄ + 2O₂  => CO₂ + 2 H₂O  complete combustion with out CO.

1 mole of methane  16 grams reacts with 2 moles of oxygen = 64 grams . to produce 2 moles of water = 36 grams.

So 16 grams of methane produces 36 grams of water.

Stoichiometry comes from the Greek “stoiechion” (element) and “metron” (to measure). As such, stoichiometry deals with determining the amounts of reactants and products that are consumed and produced within a given chemical reaction.

The stoichiometric coefficient of any species that does not participate in a given chemical reaction is zero.

The principles of stoichiometry are based upon the law of conservation of mass. Matter can neither be created nor destroyed, so the mass of every element present in the product(s) of a chemical reaction must be equal to the mass of each and every element present in the reactant(s).

Mass of 1 mole of NaOH = 23 + 16 + 1 = 40

As we know that the limiting reagent is the substance that is totally consumed in reaction. So when we take 2 moles of H₂ and O₂ then the H₂ molecules are totally consumed in the reaction. So H₂ is the limiting reagent.

Neon's atomicity is 1 Ozone's atomicity is 3 Oxygen's atomicity is 2 Carbon monoxide's atomicity is 2 Now Ozone has more atom in a molecule than any other gas in the options. So in 1 mole or 6.022×10²³ Ozone has more atom.

Mass of C=12g
Mass of H =1g
Mass of O =16g
Thus, 
Mass of C₆H₁₂O₆= 12×6+1×12+16×6
=72+12+96
=180g

Balanced equation for reaction between BaCl₂ and Na₃PO₄ is as follows:

3BaCl₂ + 2Na₃PO₄ → Ba₃(PO₄)₂  + 6NaCl

3 moles of BaCl₂ react with 2 moles of Na₃PO₄ to give 1 mole of Ba₃(PO₄)₂

0.5 moles of BaCl₂ will react with (2/3) x 0.5 = 0.33 moles of Na₃PO₄

Available moles of Na₃PO₄ = 0.2

So, Na₃PO₄ is the limiting reagent

Now, 2 moles of Na₃PO₄ give 1 mole of Ba₃(PO₄)₂

So, 0.2 moles of Na₃PO₄ will give ½ x 0.2 = 0.1 mole of Ba₃(PO₄)₂

Hence, maximum number of moles of Ba₃(PO₄)₂ formed = 0.1

The atomic masses of most elements are fractional because they exist of a mixture of Isotopes of different masses. the fractional atomic masses arise because of this mixture.
Mass =total mass of all atoms/number of atom.

A + B → AB divide given moles of each reactant by their stoichiometric coefficient , the one with least ratio is limit reagents divide with their co efficient A=2/1 =2 B=3/1 =3. So A is the limiting reagent.

1mole of Mg gives 1mole water so, to produce 12.34 moles of water we required 12.34mole of Mg.

A molecule is an electrically neutral group of two or more atoms held together by chemical bonds. Molecules are distinguished from ions by their lack of electrical charge.

1 mole of hydrogen (about 2 g) occupies a volume of 22.4 L at S.T.P 
Hence, weight of 20 L of H2 at S.T.P = (2 x 20)/22.4 = 1.8g