Answer:
a) Q = 2047.8 J (ΔH is negative because it's an exothermic reaction)
b) ΔH = -12.7 kJ /mol
Explanation:
Step 1: Data given
Molar mass of X = 78.2 g/mol
In a constant-pressure calorimeter, 12.6 g of X is dissolved in 337 g of water at 23.00 °C.
The temperature rise to 24.40 °C
The specific heat of the solution = 4.184 J/g°C
Step 2: Calculate the total mass
Total mass of the solution is given by
Total mass = 12.6 grams + 337 grams = 349.6 grams
Step 3: Calculate heat
Q = m*c*ΔT
⇒ m = the total mass = 349.6 grams
⇒ c = the specific heat of solution = 4.184 J/g°C
⇒ ΔT = The change of temperature = T2 - T1 = 24.40 - 23.00 = 1.40 °C
Q = 2047.8 J (ΔH is negative because it's an exothermic reaction)
What is the enthalpy of the reaction?
Calculate number of moles = mass/ molar mass
Moles X = 12.6 grams / 78.2 g/mol
Moles X = 0.161 moles
ΔH = -2047.8 J / 0.161 moles
ΔH = -12719.3 J/mol = -12.7 kJ /mol
A solution prepared by dissolving12.6 g of X in 337 g of water, whose temperature increases from 23.00 °C to 24.00 °C, absorbs 2.05 × 10³ J of heat. The enthalpy of the reaction is -12.7 kJ/mol.
We have a solution prepared by dissolving 12.6 g of X (solute) in 337 g of water (solvent). The mass of the solution (m) is:
The temperature of the solution increases from 23.00 °C to 24.40 °C. Assuming that the solution has the same specific heat as water (c = 4.184 J/(g·°C)), we can calculate the heat absorbed (Q) by the solution using the following expression.
According to the law of conservation of energy, the sum of the heat absorbed by the solution and the heat released by the reaction is zero.
The dissolution of 12.6 g of X (molar mass 78.2 g/mol) leads to the release of 2.05 × 10³ J (hence the negative sign). The enthalpy of the reaction is
A solution prepared by dissolving12.6 g of X in 337 g of water, whose temperature increases from 23.00 °C to 24.00 °C, absorbs 2.05 × 10³ J of heat. The enthalpy of the reaction is -12.7 kJ/mol.
You can learn more about calorimetry here: brainly.com/question/16104165
Answer:
Explanation:
H₂O(ℓ) ⟶ H₂O(g)
Data:
T = 25 °C
ΔG° = 8.6 kJ·mol⁻¹
Calculations:
T = (25 + 273.15) K = 298.15 K
Standard pressure is 1 bar.
Answer:
Option (A) saturated and is at equilibrium with the solid KCl
Explanation:
A saturated solution is a solution which can not dissolve more solute in the solution.
From the question given above, we can see that the solution is saturated as it can not further dissolve any more KCl as some KCl is still visible in the flask.
Equilibrium is attained in a chemical reaction when there is no observable change in the reaction system with time. Now, observing the question given we can see that there is no change in flask as some KCl is still visible even after thorough shaking. This simply implies that the solution is in equilibrium with the KCl solid as no further dissolution occurs.
Elements
Liquids
Crystals
Oxygen
Answer:
elements bruh
Explanation:
All living and nonliving things are made up of a combination of elements.
All living and nonliving things are made up of a combination of elements. Elements are pure substances that cannot be broken down into simpler substances and are the building blocks of matter. Examples of elements include oxygen, carbon, hydrogen, and nitrogen. These elements combine in different ways to form the various substances we see around us in the natural world.
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b) is has decreased
c)it has remained uncharged
d) it has at minimum been halved
Answer is: a) is has increased.
There are two types of reaction:
1) endothermic reaction (chemical reaction that absorbs more energy than it releases).
For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.
2) exothermic reaction (chemical reaction that releases more energy than it absorbs).
For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.
A.focus point
B.seismic wave
C.epicenter
Answer:
I think its epicenter
Explanation:
The epicenter is the point on the earth's surface vertically above the hypocenter, point in the crust where a seismic rupture begins.