From the following reactions, calculate how much F2 (in gm) will be consumed to produce 1 kg of (CF2)n ? 2CoF2 + F2 → 2CoF3 (CH2)n + 4nCoF3 → (CF2)n + 2nHF + 4nCoF2 (Express your answer as a sum of all digits till you get single digit answer.)

(1)	0
(2)	1
(3)	2
(4)	3
(5)	4
(6)	5
(7)	6
(8)	7
(9)	8
(10)	9

To determine how much fluorine gas (F2) is needed to produce 1 kg of (CF2)n, we first need to analyze the chemical reactions provided and calculate the stoichiometry involved. Let's break this down step by step.

Understanding the Reactions

We have two reactions to consider:

• 2CoF2 + F2 → 2CoF3
• (CH2)n + 4nCoF3 → (CF2)n + 2nHF + 4nCoF2

Step 1: Analyzing the First Reaction

In the first reaction, we see that 1 mole of F2 is required to produce 2 moles of CoF3. This means that for every mole of F2, we generate 2 moles of CoF3.

Step 2: Analyzing the Second Reaction

In the second reaction, CoF3 is consumed to produce (CF2)n. The stoichiometry here indicates that for every 4 moles of CoF3, we produce 1 mole of (CF2)n. Therefore, we need to find out how many moles of CoF3 are required to produce 1 kg of (CF2)n.

Calculating Molar Masses

Next, we need to calculate the molar mass of (CF2)n. The molar mass of carbon (C) is approximately 12 g/mol, and for fluorine (F), it is about 19 g/mol. Thus, the molar mass of (CF2)n can be expressed as:

Molar mass of (CF2)n = 12 + 2(19) = 12 + 38 = 50 g/mol

Step 3: Finding Moles of (CF2)n

To find out how many moles of (CF2)n are in 1 kg (or 1000 g), we use the formula:

Moles of (CF2)n = Mass / Molar Mass

Moles of (CF2)n = 1000 g / 50 g/mol = 20 moles

Determining Moles of CoF3 Required

From the second reaction, we know that 4 moles of CoF3 produce 1 mole of (CF2)n. Therefore, to produce 20 moles of (CF2)n, we need:

Moles of CoF3 = 20 moles (CF2)n × 4 moles CoF3 / 1 mole (CF2)n = 80 moles CoF3

Step 4: Finding Moles of F2 Required

Now, we go back to the first reaction. Since 1 mole of F2 produces 2 moles of CoF3, we can calculate the moles of F2 needed for 80 moles of CoF3:

Moles of F2 = 80 moles CoF3 × 1 mole F2 / 2 moles CoF3 = 40 moles F2

Calculating the Mass of F2

The molar mass of F2 is approximately 38 g/mol (since F is 19 g/mol). Therefore, the total mass of F2 required is:

Mass of F2 = Moles × Molar Mass = 40 moles × 38 g/mol = 1520 g

Final Calculation

Now, we need to express the answer as a sum of all digits until we get a single-digit answer:

• 1 + 5 + 2 + 0 = 8

Thus, the final answer is 8.