The Reaction Of Zinc Metal And Hydrochloric Acid Produces Hydrogen Gas And Zinc Chloride. Zn(S) + HCI(Ag) → ZnCl2(Ag) + H2(G) Write The Balanced Chemical Equation For The Following Reaction. Phases Are Optional. Solid Calcium Chlorate Decomposes To Form Solid Calcium Chloride And Oxygen Gas. Calcıof (S) CaCl2 (S) + 30%) Balance The Following Equations By
1=The reaction of zinc metal and hydrochloric acid produces hydrogen gas and zinc chloride.
2=Write the balanced chemical equation for the following reaction. Phases are optional. Solid calcium chlorate decomposes to form solid calcium chloride and oxygen gas.
3==Balance the following equations by inserting coefficients as needed.
The Correct Answer and Explanation is :
1. Reaction of Zinc Metal and Hydrochloric Acid
The given reaction involves the reaction of zinc metal (Zn) with hydrochloric acid (HCl) to produce zinc chloride (ZnCl₂) and hydrogen gas (H₂).
Unbalanced Equation: Zn(s)+HCl(aq)→ZnCl2(aq)+H2(g)\text{Zn}(s) + \text{HCl}(aq) \rightarrow \text{ZnCl}_2(aq) + \text{H}_2(g)
Balanced Equation:
To balance the equation, we need to ensure that the number of atoms of each element on the left side of the equation is equal to the number of atoms on the right side.
- Zinc (Zn) is already balanced, with one zinc atom on both sides.
- On the right side, zinc chloride has two chlorine atoms (Cl), so we need two HCl molecules on the left side to balance the chlorine atoms.
- Hydrogen (H) is on the left in HCl and on the right in H₂. Since there are two hydrogen atoms on the right side of the equation in H₂, we need two HCl molecules on the left side to balance the hydrogens.
Thus, the balanced equation is:
Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)\text{Zn}(s) + 2\text{HCl}(aq) \rightarrow \text{ZnCl}_2(aq) + \text{H}_2(g)
2. Decomposition of Calcium Chlorate
The second reaction involves the decomposition of solid calcium chlorate (Ca(ClO₃)₂) into solid calcium chloride (CaCl₂) and oxygen gas (O₂).
Unbalanced Equation: Ca(ClO3)2(s)→CaCl2(s)+O2(g)\text{Ca(ClO}_3\text{)}_2(s) \rightarrow \text{CaCl}_2(s) + \text{O}_2(g)
Balanced Equation:
- Start by balancing calcium (Ca). There is one calcium atom on both sides.
- Next, balance chlorine. On the left, there are two chlorine atoms (from Ca(ClO₃)₂), and on the right, CaCl₂ contains two chlorine atoms. Therefore, chlorine is already balanced.
- Now, focus on oxygen. On the left side, there are six oxygen atoms (from two chlorate ions, each containing three oxygen atoms), and on the right side, O₂ is the product, which means there are two oxygen atoms per molecule of oxygen gas. To balance the oxygen atoms, place a coefficient of 3 in front of O₂ on the right side.
Thus, the balanced equation is:
Ca(ClO3)2(s)→CaCl2(s)+3O2(g)\text{Ca(ClO}_3\text{)}_2(s) \rightarrow \text{CaCl}_2(s) + 3\text{O}_2(g)
3. General Balancing Explanation
To balance chemical equations, you follow a systematic approach:
- Write the unbalanced equation: Begin by writing the formula for each reactant and product.
- Balance the elements one at a time: Start with elements that appear in only one reactant and one product, and balance them by adjusting the coefficients (numbers placed before compounds or elements).
- Balance oxygen and hydrogen last: These elements often appear in multiple compounds and are more difficult to balance. Oxygen is typically balanced last in combustion reactions, while hydrogen is usually adjusted after oxygen.
- Check your work: After balancing the equation, verify that the number of atoms of each element is the same on both sides of the equation.
By carefully applying these steps, the chemical equation becomes balanced, ensuring that mass is conserved and the law of conservation of mass holds true.
In the cases above:
- The reaction between zinc and hydrochloric acid is balanced by adjusting the coefficient of HCl.
- The decomposition of calcium chlorate is balanced by adjusting the coefficient of oxygen gas.