Explanation:
Molar mass
The mass present in one mole of a specific species .
The molar mass of a compound , can easily be calculated as the sum of the all the individual atom multiplied by the number of total atoms .
(a) P₄
Molar mass of of the atoms are -
Phosphorous , P = 31 g/mol
Molecular mass of P₄ = ( 4 * 31 ) = 124 g/mol .
(b) H₂O
Molar mass of of the atoms are -
Hydrogen , H = 1 g/mol
oxygen , O = 16 g/mol.
Molecular mass of H₂O = ( 2 * 1 ) + ( 1 * 16 ) = 18 g/mol
(c) Ca(NO₃)₂
Molar mass of of the atoms are -
calcium , Ca = 40 g/mol
nitrogen, N = 14 g/mol
oxygen , O = 16 g/mol.
Molecular mass of Ca(NO₃)₂ = ( 1 * 40 ) + ( 2 * 14 ) + ( 6 * 16 ) = 164 g/mol.
(d)CH₃CO₂H (acetic acid)
Molar mass of of the atoms are -
Carbon , C = 12 g/mol.
oxygen , O = 16 g/mol.
Hydrogen , H = 1 g/mol
Molecular mass of CH₃CO₂H =( 2 * 12 ) + (2 * 16 ) + (4 * 1 ) = 60 g/mol.
(e) C₁₂H₂₂O₁₁ (sucrose, cane sugar).
Molar mass of of the atoms are -
Carbon , C = 12 g/mol.
oxygen , O = 16 g/mol.
Hydrogen , H = 1 g/mol
Molecular mass of C₁₂H₂₂O₁₁ = (12 * 12 ) + ( 22 * 1 ) + ( 11 * 16 ) = 342 g/mol.
Ca + 2HCl = CaCl₂ + H₂
m(Ca)=60 g
c=1.25 mol/l
M(Ca)=40g/mol
v-?
m(Ca)/M(Ca)=m(HCl)/[2M(HCl)]=n(HCl)/2
n(HCl)=2m(Ca)/M(Ca)
n(HCl)=cv
cv=2m(Ca)/M(Ca)
v=2m(Ca)/{cM(Ca)}
v=2·60g/mol/{1.25mol/l·40g/mol}=2.4 l = 2400 ml
2400 milliliters of a 1.25 molar HCl solution would be needed
Isotopes are composed of the same atoms but are arranged differently
Answer:
=<em><u> 0.42 moles of CO2 </u></em>
Explanation:
From Avogadro's constant
6.02×10^23 molecules are in 1 mole of CO2
2.54×10^23 molecules will be in
=[(2.54×10^23) ÷ (6.02×10^23)]
= 0.42 moles of CO2
Answer: Option (B) is the correct answer.
Explanation:
Equilibrium constant is defined as the relationship present between the amounts of products and reactants which are there at equilibrium in a reversible chemical reaction at a given temperature.
For example, 
Mathematically, ![K_{eq} = [C][D]](https://tex.z-dn.net/?f=K_%7Beq%7D%20%3D%20%5BC%5D%5BD%5D)
As the value of equilibrium constant depends on rate constants of the forward and reverse reactions. And, this rate of reaction also changes with change in pressure and temperature.
Therefore, it will also lead to change in equilibrium constant but it does not depend on initial amount pf reactants.
Thus, we can conclude that in general, the value of the equilibrium constant for a chemical reaction does NOT depend on the initial amounts of reactants present.
