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3 years ago

Diluting sulfuric acid with water is highly exothermic:

Chemistry

1 answer:

elena-14-01-66 [18.8K]3 years ago

8 0

Answer:

The correct answer is 51.2 degree C.

Explanation:

The standard enthalpy for H₂SO₄ (l) is -814 kJ/mole and the standard enthalpy for H₂SO₄ (aq) is -909.3 kJ/mole.

Now the dHreaction = dHf (product) - dHf (reactant)

= -909.3 - (-814)

dHreaction or q = -95.3 kJ of energy will be used for dissociating one mole of H₂SO₄.

The heat change in calorimetry can be determined by using the formula,

q = mass * specific heat capacity * change in temperature -----------(i)

Based on the given information, the density of H₂SO₄ is 1.060 g/ml

The volume of H₂SO₄ is 1 Liter

Therefore, the mass of H₂SO₄ will be, density/Volume = 1.060 g/ml / 1 × 10⁻³ ml = 1060 grams

The initial temperature given is 25.2 degrees C, or 273+25.2 = 298.2 K, let us consider the final temperature to be T₂.

ΔT = T₂ -T₁ = T₂ - 298.2 K

Now putting the values in equation (i) we get,

95.3 kJ = 1060 grams × 3.458 j/gK (T₂ - 298.2 K) (the specific heat capacity of the final solution is 3.458 J/gK)

(T₂ - 298.2 K) = 95300 J / 1060 × 3.458 = 26 K

T₂ = 298.2 K + 26 K

T₂ = 324.2 K or 324.2 - 273 = 51.2 degree C.

You might be interested in

How do you know what numbers in a chemical formula are significant

bulgar [2K]

Answer:

All the numbers in a chemical formula are significant, It is because the numbers in a chemical formula denote the number of different atoms present in the particular compound.

For example in H2SO4 there are 2 H 1 S and 4 O. This means 1 H2SO4 has 2 hydrogen 1 sulphur and 4 oxygen.

3 0

3 years ago

Here is Beck's address:

777dan777 [17]

Hi! My answer would be D, USA.

Explanation:

We are provided with 5 pieces of an address. They are as followed.

12 Riverdale Lane, Apartment A, San Jose, California, and USA.

Imagine each of the five parts of Beck's address represents Earth, the Milky Way, the moon, the solar system, or the universe, based on their sizes. Which of the following parts of Beck's address would represent the solar system?

If we have to plug in Earth, the Milky Way, the moon, the solar system, and the universe, (all based on size,) we would first start with what "Apartment A" would be in this scenario. Apartment A is the smallest piece we have to work with, and so is the moon. This leads me to believe that the Moon should be plugged into Apartment A. Now, 12 Riverdale Lane is most likely going to be the Earth, since it is the second smallest one on our list. San Jose would turn into the Sun, California represents the Milky Way, and USA represents the solar system.

I sincerely hope I helped!

Have a wonderful day :)

~AmbitiousAndProud

3 0

3 years ago

Read 2 more answers

The oxidation of Cu₂O(s) to CuO(s) is an exothermic process:

Alex73 [517]

Answer:

w = 7376.6 J

Explanation:

To calculate the work done in the system, we need first to calculate the number of moles of all compounds.

The following expression, that comes from the 1° law of thermodynamic, will help you to get the work:

w = ΔnRT

Where:

Δn: difference in the number of moles between products and reactants

R: constant universal of gases (8.314 J / mol K)

T: Temperature in Kelvin.

As we are doing this reaction in STP, then the Pressure is 1 atm, and temperature is 0 °C or 273 K.

Now, we already have the moles of Cu₂O, let's see, according to the balanced reaction, how many moles we should have of O₂ and CuO.

If 1 mole of O₂ reacts with 2 moles of Cu₂O then 6.5 moles of Cu₂O will be:

moles O₂ = 6.5 moles Cu₂O * (1 mole O₂/2 moles Cu₂O) = 3.25 moles O₂

If 2 moles of Cu₂O produces 4 moles of CuO, then 6.5 moles will be:

moles CuO = 6.5 moles Cu₂O*(4 moles CuO/2 moles Cu₂O) = 13 moles CuO

Now that we have the moles, let's calculate the value of Δn.

Δn = moles product - moles reactants

Δn = 13 - (6.5 + 3.25) = 3.25 moles

Now, we can calculate the work done in the system:

w = 3.25 * (8.314 * 273)

Hope this helps

8 0

3 years ago

Based on the information provided in the graph, we can see that as the independent variable increases,

Gnom [1K]

Well I have no clue on what your class is doing but to me, it looks like B. the dependent variable also increases

4 0

3 years ago

Read 2 more answers

How many moles of potassium nitrate are required to make 550 mL of a 2.1M solution?

stira [4]

Answer:

1.155 moles of potassium nitrate are required to make 550 mL of a 2.1M solution.

Explanation:

In a mixture, the chemical present in the greatest amount is called a solvent, while the other components are called solutes.

Molarity is a unit of concentration of a solution and indicates the amount of moles of solute that appear dissolved in each liter of the mixture. In other words, the Molarity (M) or Molar Concentration is the number of moles of solute that are dissolved in a given volume.

The Molarity of a solution is determined by the following expression:

$Molatity( M)=\frac{number of moles of solute}{Volume}$

Molarity is expressed in units ( $\frac{moles}{liter}$ ).

In this case:

Molarity= 2.1 M
number of moles of solute= ?
Volume= 550 mL= 0.550 L (being 1L=1000 mL)

Replacing:

$2.1 M= 2.1 \frac{moles}{liter} =\frac{number of moles of solute}{0.550 liters}$

Solving:

number of moles of solute= 2.1 M* 0.550 L

number of moles of solute= 1.155 moles

1.155 moles of potassium nitrate are required to make 550 mL of a 2.1M solution.

4 0

3 years ago