To balance chemical equations, you should just remember that the number of atoms of an element in the reactant side must be equal to the number of atoms of the same element in the product side. The order of the substances doesn't matter. What is important that the equation balances.
Answer:Increased the number of molecular collisions and increased the reaction rate
Explanation:
A positive change atom of hydrogen-ion. A normal hydrogen atomic nucleus
Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Precipitation is a type of displacement reaction in which one the products is formed in the solid state.

Answer:
The balanced equation is: H2 (g) +Cl2 (g) →2HCl (g)
Explanation:
Balancing chemical equation refers to balancing the stoichiometric coefficients on the reactants and products side. This must be done as the chemical equation obeys the law of conservation of mass and momentum.
The representation of a chemical reaction in the form of substances is known as a chemical equation. The equation in which the number of atoms of all the molecules is equal on both sides of the equation is known as a balanced chemical equation. The Law of conservation of mass governs the balancing of a chemical equation.
Given chemical equation
The balanced chemical equation for the hydrogen + chlorine -> Hydrogen Chloride.
H2 + Cl2 → 2HCl
The equation is balanced as on the reactants side there are two hydrogens present and the same on the products side. For chlorine as well the same thing goes two chlorine atoms on the reactants side and two on the products side.