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3 years ago

Calculate the number of kilojoules to warm 125 g of iron from 23.5 degrees C to 78 degrees C

1 answer:

5 0

The heat capacity of iron is 0.45J/g°C.
We calculate the heat using the equation:
ΔH = m cp ΔT
where
<span>m is the mass
ΔH is enthalphy or the heat required
cp is the heat capacity
</span><span>ΔT is the change in temperature
</span>So,
<span>ΔH = m cp ΔT = (125g) (0.45 J/g</span>°C) (75°C - 23.5<span>°C)
</span><span>ΔH = 2896.875 J
</span>
Dividing by 1000 to convert to kJ,
<span>ΔH = 2.897 kJ</span>

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What is the empirical formula of propene CH3 CH2 CH2

kiruha [24]

Answer:

Explanation:

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3 = 3
6 = 2 x 3

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3CH
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Molecular Formula / No. of moles
C₃H₆ / 3
<u>CH</u>

<u></u>

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1 year ago

Iodine, I2, is a solid at room temperature but sublimes (converts from a solid into a gas) when warmed. What is the temperature

Stels [109]

<h3>Answer:</h3>

382.63 K

<h3>Explanation:</h3>

We are given;

Volume of Iodine as 71.4 mL
Mass of Iodine as 0.276 g
Pressure of Iodine as 0.478 atm

We are required to calculate the temperature of Iodine

We are going to use the ideal gas equation;

According to the ideal gas equation; PV = nRT, where R is the ideal gas constant, 0.082057 L.atm/mol.K.

Rearranging the formula;

T = PV ÷ nR

But, n, the number of moles = Mass ÷ Molar mass

Molar mass of iodine = 253.8089 g/mol

Thus, n = 0.276 g ÷ 253.8089 g/mol

= 0.001087 moles

Therefore;

T = (0.478 atm × 0.0714 L) ÷ (0.001087 moles × 0.082057)

= 382.63 K

Thus, the temperature of Iodine in Kelvin is 382.63 K

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3 years ago

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guapka [62]

Answer: C

Explanation:

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nordsb [41]

Answer :

<h2>Multicellular organisms</h2>

Explanation :

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