Which of the following equations depicts a balanced equation, na2co3+2hcl=2nacl+co2+h2o, naco3+hcl=2nacl+co2+1h2o, 2na2co3+3hcl=3nacl+2co2+h2o or na2co3+hcl=nacl+co2+h2o? ?

Option A is the Answer

Explanation:

Balancing is making the number of atoms of each element same on both the sides  (reactant and product side).

To find the number of atoms of each element we multiply coefficient × subscript  

For example contains  

5 × 1 = 5 , Ca atoms and

5 × 2 = 10, Cl atoms  

If there is a bracket in the chemical formula  

For example we multiply coefficient × subscript × number outside the bracket.......... to find the number of atoms  (Please note: 3 is the coefficient, and if there is no number given then 1 will be the coefficient )

So 3 × 3 = 9, Ca atoms  

3 × 1 × 2 = 6, P atoms  

3 × 4 × 2 = 24, O atoms are present.

A)

Reactant Side       # of atoms of each element      Product Side

2                                            Na                                      2

1                                             C                                        1

3                                             O                                       3

2                                             H                                       2

2                                             Cl                                       2

Balanced

B)

(Chemical formula given for Sodium carbonate  is not correct)

Na2CO3 is the correct formula

C)

(Not balanced correctly)

Reactant Side       # of atoms of each element      Product Side

4                                            Na                                      3

2                                             C                                       2

6                                             O                                       5

3                                             H                                       2

3                                             Cl                                      3

Not same on both the sides

Hence  UnBalanced  

D)

Unbalanced

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.