Question

q. 2. when methane gas burns in oxygen gas, carbon dioxide gas and water vapors are formed. ans. q. 3. zinc metal reacts with copper sulfate solution to form zinc sulfate solution and solid copper. ans. q. 4. sodium metal reacts with chlorine gas to form solid sodium chloride. ans. q. 5. potassium metal reacts with iodine gas to form solid potassium iodide. ans.

Explanation:

To solve these problems, we need to write the balanced chemical equations for each reaction. Let's tackle each question one by one:

Q.2: When Methane gas burns in Oxygen gas, Carbon dioxide gas and water vapors are formed.

Step 1: Write the unbalanced equation

Methane is \( CH_4 \), Oxygen is \( O_2 \), Carbon dioxide is \( CO_2 \), and water is \( H_2O \).
Unbalanced equation: \( CH_4 + O_2
ightarrow CO_2 + H_2O \)

Step 2: Balance the carbon atoms

There is 1 C on the left and 1 C on the right, so C is balanced.

Step 3: Balance the hydrogen atoms

There are 4 H on the left (\( CH_4 \)) and 2 H on the right (\( H_2O \)). Multiply \( H_2O \) by 2:
\( CH_4 + O_2
ightarrow CO_2 + 2H_2O \)

Step 4: Balance the oxygen atoms

Now, there are 2 O on the left (\( O_2 \)) and \( 2 + 2 = 4 \) O on the right (\( CO_2 + 2H_2O \)). Multiply \( O_2 \) by 2:
\( CH_4 + 2O_2
ightarrow CO_2 + 2H_2O \)

Q.3: Zinc metal reacts with copper sulfate solution to form zinc sulfate solution and solid copper.

Step 1: Write the unbalanced equation

Zinc is \( Zn \), copper sulfate is \( CuSO_4 \), zinc sulfate is \( ZnSO_4 \), and copper is \( Cu \).
Unbalanced equation: \( Zn + CuSO_4
ightarrow ZnSO_4 + Cu \)

Step 2: Check for balance

• Zn: 1 on left, 1 on right
• Cu: 1 on left, 1 on right
• S: 1 on left, 1 on right
• O: 4 on left, 4 on right

This equation is already balanced.

Q.4: Sodium metal reacts with chlorine gas to form solid sodium chloride.

Step 1: Write the unbalanced equation

Sodium is \( Na \), chlorine gas is \( Cl_2 \), and sodium chloride is \( NaCl \).
Unbalanced equation: \( Na + Cl_2
ightarrow NaCl \)

Step 2: Balance the chlorine atoms

There are 2 Cl on the left (\( Cl_2 \)) and 1 Cl on the right (\( NaCl \)). Multiply \( NaCl \) by 2:
\( Na + Cl_2
ightarrow 2NaCl \)

Step 3: Balance the sodium atoms

Now, there is 1 Na on the left and 2 Na on the right. Multiply \( Na \) by 2:
\( 2Na + Cl_2
ightarrow 2NaCl \)

Q.5: Potassium metal reacts with iodine gas to form solid potassium iodide.

Step 1: Write the unbalanced equation

Potassium is \( K \), iodine gas is \( I_2 \), and potassium iodide is \( KI \).
Unbalanced equation: \( K + I_2
ightarrow KI \)

Step 2: Balance the iodine atoms

There are 2 I on the left (\( I_2 \)) and 1 I on the right (\( KI \)). Multiply \( KI \) by 2:
\( K + I_2
ightarrow 2KI \)

Step 3: Balance the potassium atoms

Now, there is 1 K on the left and 2 K on the right. Multiply \( K \) by 2:
\( 2K + I_2
ightarrow 2KI \)

Final Answers:

• Q.2: \( \boldsymbol{CH_4 + 2O_2

ightarrow CO_2 + 2H_2O} \)

• Q.3: \( \boldsymbol{Zn + CuSO_4

ightarrow ZnSO_4 + Cu} \)

• Q.4: \( \boldsymbol{2Na + Cl_2

ightarrow 2NaCl} \)

• Q.5: \( \boldsymbol{2K + I_2

ightarrow 2KI} \)

Answer:

To solve these problems, we need to write the balanced chemical equations for each reaction. Let's tackle each question one by one:

Q.2: When Methane gas burns in Oxygen gas, Carbon dioxide gas and water vapors are formed.

Step 1: Write the unbalanced equation

Methane is \( CH_4 \), Oxygen is \( O_2 \), Carbon dioxide is \( CO_2 \), and water is \( H_2O \).
Unbalanced equation: \( CH_4 + O_2
ightarrow CO_2 + H_2O \)

Step 2: Balance the carbon atoms

There is 1 C on the left and 1 C on the right, so C is balanced.

Step 3: Balance the hydrogen atoms

There are 4 H on the left (\( CH_4 \)) and 2 H on the right (\( H_2O \)). Multiply \( H_2O \) by 2:
\( CH_4 + O_2
ightarrow CO_2 + 2H_2O \)

Step 4: Balance the oxygen atoms

Now, there are 2 O on the left (\( O_2 \)) and \( 2 + 2 = 4 \) O on the right (\( CO_2 + 2H_2O \)). Multiply \( O_2 \) by 2:
\( CH_4 + 2O_2
ightarrow CO_2 + 2H_2O \)

Q.3: Zinc metal reacts with copper sulfate solution to form zinc sulfate solution and solid copper.

Step 1: Write the unbalanced equation

Zinc is \( Zn \), copper sulfate is \( CuSO_4 \), zinc sulfate is \( ZnSO_4 \), and copper is \( Cu \).
Unbalanced equation: \( Zn + CuSO_4
ightarrow ZnSO_4 + Cu \)

Step 2: Check for balance

• Zn: 1 on left, 1 on right
• Cu: 1 on left, 1 on right
• S: 1 on left, 1 on right
• O: 4 on left, 4 on right

This equation is already balanced.

Q.4: Sodium metal reacts with chlorine gas to form solid sodium chloride.

Step 1: Write the unbalanced equation

Sodium is \( Na \), chlorine gas is \( Cl_2 \), and sodium chloride is \( NaCl \).
Unbalanced equation: \( Na + Cl_2
ightarrow NaCl \)

Step 2: Balance the chlorine atoms

There are 2 Cl on the left (\( Cl_2 \)) and 1 Cl on the right (\( NaCl \)). Multiply \( NaCl \) by 2:
\( Na + Cl_2
ightarrow 2NaCl \)

Step 3: Balance the sodium atoms

Now, there is 1 Na on the left and 2 Na on the right. Multiply \( Na \) by 2:
\( 2Na + Cl_2
ightarrow 2NaCl \)

Q.5: Potassium metal reacts with iodine gas to form solid potassium iodide.

Step 1: Write the unbalanced equation

Potassium is \( K \), iodine gas is \( I_2 \), and potassium iodide is \( KI \).
Unbalanced equation: \( K + I_2
ightarrow KI \)

Step 2: Balance the iodine atoms

There are 2 I on the left (\( I_2 \)) and 1 I on the right (\( KI \)). Multiply \( KI \) by 2:
\( K + I_2
ightarrow 2KI \)

Step 3: Balance the potassium atoms

Now, there is 1 K on the left and 2 K on the right. Multiply \( K \) by 2:
\( 2K + I_2
ightarrow 2KI \)

Final Answers:

• Q.2: \( \boldsymbol{CH_4 + 2O_2

ightarrow CO_2 + 2H_2O} \)

• Q.3: \( \boldsymbol{Zn + CuSO_4

ightarrow ZnSO_4 + Cu} \)

• Q.4: \( \boldsymbol{2Na + Cl_2

ightarrow 2NaCl} \)

• Q.5: \( \boldsymbol{2K + I_2

ightarrow 2KI} \)