Answer:
H₂O + CO₂ → H₂CO₃
Option D is correct.
Law of conservation of mass:
According to this law, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Now we will apply this law to given chemical equations:
A) H₂ + O₂ → H₂O
There are two H and two O atoms present on left side while on right side only one O and two H atoms are present so mass in not conserved. This option is incorrect.
B) Mg + HCl → H₂ + MgCl₂
In this equation one Mg, one H and one Cl atoms are present on left side of equation while on right side two H, one Mg and two chlorine atoms are present. This equation also not follow the law of conservation of mass.
C) KClO₃ → KCl + O₂
There are one K, one Cl and three O atoms are present on left side of equation while on right side one K one Cl and two oxygen atoms are present. This equation also not following the law of conservation of mass.
D) H₂O + CO₂ → H₂CO₃
There are two hydrogen, one carbon and three oxygen atoms are present on both side of equation thus, mass remain conserved. This option is correct.
You can simply subtract the atomic number from the mass number in order to find the number of neutrons.
a core of protons and neutrons surrounds by electrons
Answer:
All the members of a group of elements have the same number of valence electrons and similar chemical properties.
Explanation:
The vertical columns on the periodic table are called groups or families because of their similar chemical behavior.
