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3 years ago

Chem timed exam, help plz

Chemistry

1 answer:

Alchen [17]3 years ago

5 0

Answer:

3.864 g of C₃H₆

Explanation:

The balanced equation for the reaction is given below:

2C₃H₆ + 9O₂ —> 6CO₂ + 6H₂O

From the balanced equation above,

2 moles of C₃H₆ reacted to produce 6 moles of CO₂

Next, we shall determine the number of mole of C₃H₆ that reacted to produce 0.276 mole of CO₂. This can be obtained as follow:

From the balanced equation above,

2 moles of C₃H₆ reacted to produce 6 moles of CO₂.

Therefore, Xmol of C₃H₆ will react to produce 0.276 moles of CO₂ i.e

Xmol of C₃H₆ = (2 × 0.276)/6

Xmol of C₃H₆ = 0.092 mole

Finally, we shall determine the mass of 0.092 mole of C₃H₆. This can be obtained as follow:

Mole of C₃H₆ = 0.092 mole

Molar mass of C₃H₆ = (12×3) + (6×1)

= 36 + 6

= 42 g/mol

Mass of C₃H₆ =?

Mass = mole × molar mass

Mass of C₃H₆ = 0.092 × 42

Mass of C₃H₆ = 3.864 g

Therefore, 3.864 g of C₃H₆ is needed for the reaction.

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Specific heat of metal = ?

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$120\times 4.184\times (24.5-21.8)=40.2\times C_{metal}\times (99.3-24.5)$

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