1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
katen-ka-za [31]
3 years ago
13

Which of the following is kept constant when using a bomb calorimeter?

Chemistry
1 answer:
trapecia [35]3 years ago
6 0
Constant Volume Calorimetry, also know as bomb calorimetry, is used to measure the heat of a reaction while holding volume constant and resisting large amounts of pressure. Although these two aspects of bomb calorimetry make for accurate results, they also contribute to the difficulty of bomb calorimetry. In this module, the basic assembly of a bomb calorimeter will be addressed, as well as how bomb calorimetry relates to the heat of reaction and heat capacity and the calculations involved in regards to these two topics.

Introduction 

Calorimetry is used to measure quantities of heat, and can be used to determine the heat of a reaction through experiments. Usually a coffee-cup calorimeter is used since it is simpler than a bomb calorimeter, but to measure the heat evolved in a combustion reaction, constant volume or bomb calorimetry is ideal. A constant volume calorimeter is also more accurate than a coffee-cup calorimeter, but it is more difficult to use since it requires a well-built reaction container that is able to withstand large amounts of pressure changes that happen in many chemical reactions.

Most serious calorimetry carried out in research laboratories involves the determination of heats of combustion ΔHcombustion" role="presentation" style="display: inline-table; font-style: normal; font-weight: normal; line-height: normal; font-size: 14.4px; text-indent: 0px; text-align: left; text-transform: none; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">ΔHcombustionΔHcombustion, since these are essential to the determination of standard enthalpies of formation of the thousands of new compounds that are prepared and characterized each month. In a constant volume calorimeter, the system is sealed or isolated from its surroundings, and this accounts for why its volume is fixed and there is no volume-pressure work done. A bomb calorimeter structure consists of the following:

Steel bomb which contains the reactantsWater bath in which the bomb is submergedThermometerA motorized stirrerWire for ignition

is usually called a “bomb”, and the technique is known as bomb calorimetry

Another consequence of the constant-volume condition is that the heat released corresponds to qv , and thus to the internal energy change ΔUrather than to ΔH. The enthalpy change is calculated according to the formula

(1.1)ΔH=qv+ΔngRT" role="presentation" style="display: inline-table; font-style: normal; font-weight: normal; line-height: normal; font-size: 14.4px; text-indent: 0px; text-align: center; text-transform: none; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; width: 10000em !important; position: relative;">ΔH=qv+ΔngRT(1.1)(1.1)ΔH=qv+ΔngRT

Δng" role="presentation" style="display: inline-table; font-style: normal; font-weight: normal; line-height: normal; font-size: 14.4px; text-indent: 0px; text-align: left; text-transform: none; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">ΔngΔng  is the change in the number of moles of gases in the reaction.

You might be interested in
The production of ethylene glycol from ethylene chlorohydrin and sodium bicarbonate ↑ is carried out in a semibatch reactor. A 1
jarptica [38.1K]

Answer:

The constant density decreases

Explanation:

As the temperature of a solvent increases, the solubility of any gas dissolved in that solvent decreases.

For example:

when the temperature of a river, lake or stream is raised high , due to discharge of hot water from some industrial process the solubility of the oxygen in the water is decreased .The fish and the other organisms that live in the water bodies such as rivers, ponds, lakes etc can survive only in the presence of oxygen and decrease in the concentration of the water due to increased temperature can lead to the death of the fish and this may in turn damage the ecosystem.

In the above example, water is considered as the solvent and the oxygen is considered as the solute. When the temperature of the solvent that is water increases, the solubility of the gas that is oxygen in the solvent decreases.

Therefore the answer is decreases

6 0
3 years ago
Read 2 more answers
Convert 5.28 x 1019 molecules of C6H1206 to grams.
nlexa [21]

Answer:

m=0.0158g

Explanation:

Hello there!

In this case, it is possible to comprehend these mass-particles problems by means of the concept of mole, molar mass and the Avogadro's number because one mole of any substance has 6.022x10²³ particles and have a mass equal to the molar mass.

In such a way, for C₆H₁₂O₆, whose molar mass is about 180.16 g/mol, the referred mass would be:

m=5.28x10^{19}molecules*\frac{1mol}{6.022x10^{23}molecules}*\frac{180.16g}{1mol}\\\\m=0.0158g

Best regards!

5 0
3 years ago
How do you know a physical change has occurred when evaporating water produces gaseous water?
levacccp [35]

Answer:

Its b its the state not anything else

6 0
3 years ago
What happens in the redox reaction below? Select all that apply.
vladimir2022 [97]

Answer:

B- Sodium loses an electron.

D- Fluorine gains an electron.

Sodium is oxidized.

Explanation:

The reaction equation is given as:

        Na  + F →  NaF

In this reaction, Na is the reducing agent. It loses an electron and then becomes oxidized. By so doing, Na becomes isoelectronic with Neon.

Fluorine gains the electron and then becomes reduced. This makes fluorine also isoelectronic with Neon.

This separation of charges on the two species leads to an electrostatic attraction which forms the ionic bonds.

6 0
2 years ago
5TH GRADE SCIENCE!!!!!!
Yuri [45]

Answer:

Phase changes that require a loss in energy are condensation and freezing.

Explanation:

4 0
3 years ago
Read 2 more answers
Other questions:
  • Hydrochloric acid reacts faster with powdered zinc than with an equal mass of zinc strips because the greater the surface area o
    15·1 answer
  • A balloon is filled with helium at sea level. The volume was measured to be 3.1 liters at a pressure of 0.97 atmosphere. If the
    7·2 answers
  • Answer the following questions about the solubility of AgCl(s). The value of Ksp for AgCl(s) is 1.8 × 10−10.
    11·1 answer
  • The same or similar results in successive measurements is a feature of which measure
    12·1 answer
  • Which of these measurements was made with the most precise measuring device: 8.1956m, 8.20m, or 8.196m?
    7·2 answers
  • Liquids and gases are matter because they take up space and have
    14·1 answer
  • Penicillin N is an antibacterial agent that contains 8.92% sulphur by mass.Which could be the molar mass of Penicillin N? a)256g
    14·1 answer
  • Which of the following is NOT an area of study in chemistry? * 1 point Biochemistry Physical chemistry Ergonomic chemistry Analy
    9·2 answers
  • Draw the Lewis dot structure for benzene
    9·2 answers
  • Melting point of a substance is what kind of property?
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!