Question

1. What Volume of HCl is generated if 3.44 g of Cl2 are reacted at STP? $H_{2} (g) + Cl_{2}(g) -\ \textgreater \ 2HCl(g)$ 2. What volume does 4.87 mol of Kr have at STP? 3. What pressure of HCl is generated if 3.44 g of Cl2 are reacted in 4.55 L at 455 K?

Answer 1

Answer:

1. 2.17 dm^3

2. 109.1 dm^3

3. 0.398 atm

Explanation:

1. Considering the equation of the reaction;

Number of moles of chlorine gas in 3.44 g= 3.44/2(35.5)= 0.0485 moles

Since we can see from the equation that

1 mole of chlorine gas yields 2(22.4) dm^3 of HCl

0.0485 moles of chlorine gas yields 0.0485 moles × 2(22.4)dm^3/1= 2.17 dm^3

2. Note that 1 mole of Kr occupies 22.4 dm^3

Therefore 4.87 moles of Kr will occupy 4.87 × 22.4 dm^3/1 = 109.1 dm^3

3. From PV= nRT

n= 0.0485 moles

V= 4.55 L

T= 455 K

P= the unknown

R= 0.082 atm dm^3K-1mol-1

P= nRT/V

P= 0.0485 moles × 0.082 atm dm^3K-1mol-1 × 455/4.55

P= 0.398 atm

Answer 2

Answer:

1) volume of HCl = 2.17 L HCl

2) volume of Kr = 109.09 L

3) Pressure of HCl = 0.796 atm

Explanation:

Step 1: Data given

Mass of Cl2 : 3.44 grams

Molar mass Cl2 = 70.9 g/mol

STP = 1atm and 273 K

Step 2: The balanced equation

H2(g) + Cl2(g) → 2HCl(g)

Step 3: Calculate moles of Cl2

Moles Cl2 = mass/ molar mass Cl2

Moles Cl2 = 3.44 grams / 70.9 g/mol

Moles Cl2 = 0.0485 moles

Step 4: Calculate moles HCl

For 1 mol H2 we need 1 mol Cl2 to produce 2 moles HCl

For 0.0485 moles Cl2 we'll have 2*0.0485 = 0.097 moles HCl

Step 5: Calculate volume of HCl

For 1 mol we have 22.4 L

For 0.097 moles we have 22.4 * 0.097 = 2.17 L HCl

Step 1: Data given

Moles of Kr = 4.87 moles

STP = 1 mol, 1atm and 273 K and 22.4 L

Step 2: Calculate volume at STP

1 mol has a volume of 22.4 L

4.87 moles has a volume of 22.4 L * 4.87 = 109.09 L

Step 1: Data given

Mass of Cl2 : 3.44 grams

Molar mass Cl2 = 70.9 g/mol

Volume = 4.55 L

Temperature = 455 K

Step 2: The balanced equation

H2(g) + Cl2(g) → 2HCl(g)

Step 3: Calculate moles of Cl2

Moles Cl2 = mass/ molar mass Cl2

Moles Cl2 = 3.44 grams / 70.9 g/mol

Moles Cl2 = 0.0485 moles

Step 4: Calculate moles HCl

For 1 mol H2 we need 1 mol Cl2 to produce 2 moles HCl

For 0.0485 moles Cl2 we'll have 2*0.0485 = 0.097 moles HCl

Step 5: Calculate pressure of HCl

p*V = n*R*T

⇒with p = the pressure of HCl = TO BE DETERMINED

⇒with V = the volume = the volume of HCl = 4.55 L

⇒with n = the moles of HCl = 0.097 moles

⇒with R = the gas constant = 0.08206 L*atm/mol*K

⇒with T = the temperature = 455 K

p = n*R*T / V

p = (0.097 moles * 0.08206L*atm/mol*K * 455 K) / 4.55 L

p = 0.796 atm