Answer:
A. 8600 J
General Formulas and Concepts:
<u>Thermochemistry</u>
Specific Heat Formula: q = mcΔT
- q is heat (in J)
- m is mass (in g)
- c is specific heat (in J/g °C)
- ΔT is change in temperature (in °C)
Explanation:
<u>Step 1: Define</u>
[Given] <em>m</em> = 1600 g
[Given] ΔT = 214 °C - 202 °C = 12 °C
[Given] <em>c</em> = 0.450 J/g °C
[Solve] <em>q</em>
<u>Step 2: Find Heat</u>
- Substitute in variables [Specific Heat Formula]: q = (1600 g)(0.450 J/g °C)(12 °C)
- Multiply [Cancel out units]: q = (720 J/°C)(12 °C)
- Multiply [Cancel out units]: q = 8640 J
<u>Step 3: Check</u>
<em>Follow sig fig rules and round. We are given 2 sig figs as our lowest.</em>
8640 J ≈ 8600 J
Topic: AP Chemistry
Unit: Thermodynamics
Answer:
THE NEW PRESSURE OF THE HELIUM GAS IS 124kPa AFTER THE VOLUME WAS INCREASED FROM 2.48 L TO 2.98 L
Explanation:
Using Boyle's law which states that at constant temperature, the pressure of a given gas is inversely proportional to the volume occupied by the gas.
Mathematically,
P1 V1 = P2 V2
P1 = 150 kPa = 150 * 10^3 Pa
V1 = 2.48 L
V2 = 2.98 L
P2 = ?
Rearranging the formula making P2 the subject of the equation, we obtain;
P2 = P1 V1 / V2
P2 = 150 * 10^3 * 2.48 / 2.98
P2 = 372 * 10 ^3 / 2.98
P2 = 124.83 * 10^3 Pa or 124.8kPa
In other words, the new pressure of the helium gas after its volume was increased from 2.48 L to 2.98 L is 124.8kPa.
The mole ratio of the reaction shows that equal volumes of hydrogen gas will be produced by the two reactions.
<h3>What is the mole ratio of a reaction?</h3>
The mole ratio of a reaction is the ratio in which the reactants and products of a given reaction occur for the reaction to proceed to completion.
The mole ratio of a reaction is also known as the stoichiometry of the reaction.
The equation of the two reactions are given below:


From the equation of the reaction reaction, an equal volume of hydrogen gas will be produced by the two reactions.
Therefore, the mole ratio of the reaction shows that equal volumes of hydrogen gas will be produced by the two reactions.
Learn more about mole ratio at: brainly.com/question/19099163
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Answer:

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