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2 years ago

How many joules of heat energy are released when 50.0 g of water are cooled from 70.00C to 60.00C?

Chemistry

1 answer:

baherus [9]2 years ago

5 0

Answer:

2090 joules are released.

Explanation:

Calorimetry is applied to this problem:

Q = m . C . (Final T° - Initial T°)

C is the Specific Heat, a constant for each substance, that determines the heat per unit mass, which is required to raise one degree Celsius.

C for water is 4.18 kJ /kg.°C

We convert the mass of water to kg

50 g . 1kg / 1000 g = 0.05 kg

Let's replace data in the formula:

Q = 0.05 kg . 4.18 kJ /kg.°C (60°C - 70°c)

Q = -2.09 kJ

As we have a negative value, heat is released. We need the |Q| for the value

2.09 kJ . 1000 J /kJ = 2090 joules

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3 element i.e carbon (C), hydrogen (H) and oxygen.

Explanation:

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2 years ago

Two types of heterogeneous mixtures are suspensions and colloids.<br>true or false<br><br>

scoray [572]

<h2>Answer:True</h2>

Explanation:

Heterogeneous mixture is a mixture with non-uniform composition.

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3 years ago

PLEASE HELP!

fgiga [73]

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2 years ago

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In a lab experiment 80.0 g of ammonia [NH3] and 120 g of oxygen are placed in a reaction vessel. At the end of the reaction 72.2

valentinak56 [21]

The percent yield of the reaction : 89.14%

<h3>Further explanation</h3>

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mol NH₃ (MW=17 g/mol):

$\dfrac{80}{17}=4.706$

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mol O₂(MW=32 g/mol) :

$\tt \dfrac{120}{32}=3.75$

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$\tt \dfrac{4.706}{4}\div \dfrac{3.75}{5}=1.1765\div 0.75\rightarrow O_2~limiting~reactant(smaller~ratio)$

mol of H₂O based on O₂ as limiting reactants :

mol H₂O :

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mass H₂O :

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2 years ago