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
grandymaker [24]
3 years ago
8

Identify each process as endothermic or exothermic and indicate the sign of H . (a) an ice cube melting (b) nail polish remover

quickly evaporating after it is accidentally spilled on the skin (c) gasoline burning within the cylinder of an automobile engine
Chemistry
1 answer:
Delicious77 [7]3 years ago
7 0

Answer:an ice cube melting ∆H=+ve

nail polish remover quickly evaporating after it is accidentally spilled on the skin ∆H=-ve

gasoline burning within the cylinder of an automobile engine ∆H=-ve

Explanation:

In an endothermic process, such as the melting of an ice cube, heat is absorbed from the surrounding. The enthalpy change is positive. The evaporation a nail polish and burning of gasoline are exothermic processes which lead to the release of heat to the surrounding. The sign of the enthalpy change in both cases is negative.

You might be interested in
Pls someone help me with this question pls
OlgaM077 [116]

Answer:

D

Explanation:

4 0
2 years ago
Read 2 more answers
Pressure is the force exerted by a substance on its container. Of the three phases of matter which one would exert the highest p
Luden [163]

Answer:

Gaseous phase exert more pressure on container.

Explanation:

Pressure:

It is the force exerted by the substance on its container.

Mathematical expression:

P = F/A

P = pressure

F = force

A = area

We know that there are phases of matter solid liquid and gas.

Gases don't have definite volume and shape and take the shape and volume of container in which it present.  Molecule of gases randomly move everywhere and occupy all available space.  The molecules of gas randomly move collide with each other and also the wall of container their kinetic energy also increased because of this collision and pressure is produced

While in case of liquid molecules are packed and they can not move freely thus did not exert pressure like gaseous molecules.

In case of solids molecules are tightly packed and form more compact structure. They can not move thus did not exert pressure to the wall of container.

Properties of gases:

Molecule of gases randomly move everywhere and occupy all available space.

Gases don't have definite volume and shape and take the shape and volume of container in which it present.

Their densities are very low as compared to the liquid and solids.

Gas molecules are at long distance from each other therefore by applying pressure gases can be compressed.

The very weak inter molecular forces are present between gas molecules.

Properties of Liquid:

Liquid have definite volume but don,t have definite shape.

Their densities are high as compared to the gases but low as compared to the solids.

In liquid, molecules are close to each other and have greater inter molecular forces as compared to the gas molecules.

Properties of solids:

Solids have definite volume and shape.

In solids molecules are tightly pack and very close to each other.

Their melting and boiling point are every high.

The densities of solids are also very high as compared to the liquid and gas.

There are very strong inter molecular forces are present between solid molecules.

6 0
3 years ago
Identify the number and kinds of atoms present in a molecule of each compound butane
ohaa [14]
The butane is a kind of alkane. And there is only carbon and hydrogen and single bonds. The formula of butane is C4H10. There are four carbon atoms and ten hydrogen atoms present in one butane molecule.
4 0
3 years ago
Calculate the energy in joules and calories required to heat 25.0 g of water from 12.5C to 25.7C
Alex Ar [27]
The heat (Q) required to raise the temp of a substance is:<span>Q=m∗Cp∗ΔT</span><span> where m is the mass of the object (25.0g in this case), Cp is the specific heat capacity of the substance (for water Cp = 1.00cal/gC, or 4.18J/gC,
and Dt is the change in temp.
You'll have to solve this twice, once with the Cp in calories, and once with the Cp in joules.
</span><span>1380.72 Joules</span>
8 0
3 years ago
How many moles are in 9.12 x 1023 molecules of sugar?​
aleksandrvk [35]

Answer:

1.514 moles

Explanation:

For this problem you want to use dimensional analysis and cancel out your molecules of sugar and be left with moles of sugar. We know that 1 mole (of anything) = 6.022 x 10 ^ 23 molecules, so we should use that conversion to help us. Start with 9.12 x 10 ^23 molecules and divide by 6.022 x 10 ^ 23 molecules, and you will be left with moles.

Hope this helps!

3 0
2 years ago
Other questions:
  • This substance should never be used to put out a petrol or oil fire
    15·1 answer
  • Is a leaf a solid,liquid or gas?​
    8·2 answers
  • Your class goes on a field trip to observe drilling machinery. The geologists at the drill site show you displays of drilled roc
    10·1 answer
  • The density of liquid mercury is 13.69 g/cm 3 . how many atoms of mercury are in a 17 ml sample? use "e" for "×10" and report th
    15·1 answer
  • It was field day at school. The sun was bright and the temperature high. Most of the students wore light colored T-shirts to sta
    7·2 answers
  • Which is not a redox reaction?
    14·1 answer
  • How can energy transfer affect the physical and chemical properties of matter?
    5·1 answer
  • Congratulations! You’ve recently received a promotion from work. Your new job is to fill rooms with certain gases. A room is fou
    11·1 answer
  • Which jobs does the respiratory system do? Select all that apply. It brings oxygen into the blood. It removes carbon dioxide was
    5·2 answers
  • Determine the theoretical yield of PbCh2
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!