Which sentence best describes what happens during a change of state from a solid to a liquid?

A. The temperature stays the same and the particle speed increases

B. The temperature increases and the particle speed stays constant.

C. The temperature decreases and the particle speed decreases.

D. The temperature stays the same and the particle speed stays constant.​

Answer:

25 centigrams is equal to 2.5 grams.

150 hectometers are 10,000 centimeters.

Explanation:

10 centigrams is equal to 0.1 gram.

25 / 10 = 2.5

1 hectometer is equal to 10,000 centimeters.

150 x 10,0000 = 1500000

Explanation:

Mass of bomb calorimeter, m = 1.5 kg = 1500 g

Temperature change of calorimeter, ΔT = - 0.985 K

Specific heat of calorimeter, c = 2.52 J/g K

To Find:

The heat of reaction for this system

Calculation:

The heat of reaction can be calculated by the given formula:

Q = mcΔT

⇒ Q = 1500 × 2.52 × (- 0.985)

⇒ Q = - 3723.3 J       (-ve sign shows heat is given by calorimeter)

- So the heat of reaction is -3723.3 J or -3.7233 kJ

Taking into account the definition of calorimetry, the heat of reaction for the system is  -3,723.3 J or -3.7233 kJ.

In first place, calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

In this way, between heat and temperature there is a direct proportional relationship.

The constant of proportionality depends on the substance that constitutes the body and its mass, and is the product of the specific heat by the mass of the body.

So, the equation that allows to calculate heat exchanges is:

Q = c× m× ΔT

where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.

In this case, you know:

Replacing in the expression to calculate heat exchanges:

Q= 2.52[tex]\frac{J}{gK}[/tex]× 1500 g× (-0.985 K)

Solving:

Q= -3,723.3 J= -3.7233 kJ

Negative sign shows heat is given by calorimeter.

In summary, the heat of reaction for the system is  -3,723.3 J or -3.7233 kJ.

Learn more abour calorimetry:

Considering the ideal gas law, the mass of hydrogen is 24.552 grams.

An ideal gas is a theoretical gas that is considered to be composed of randomly moving point particles that do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:

P× V = n× R× T

In this case, you know:

Replacing in the ideal gas law:

1 atm× 1000 L = n× 0.082[tex]\frac{atmL}{molK}[/tex]× 298 K

Solving:

[tex]n=\frac{1 atmx1000 L}{0.082 \frac{atmL}{molK}x298 K}[/tex]

n= 40.92 mol

The mol of syngas mixture is 40.92 mol.

Syngas mixture contains 30.0% hydrogen. So, there is a mol fraction of [tex]x_{hydrogen} =[/tex]0.3 . Thus, the mols of hydrogen in syngas mixture is calculated as:

40.92 moles of syngas mixture× 0.3= 12.276 moles of hydrogen

Finally, being the molar mass of hydrogen H₂ 2 [tex]\frac{g}{mole}[/tex], then the mass is:

[tex]12.276 molesx\frac{2 grams}{1 mole}[/tex]= 24.552 grams

In summary, the mass of hydrogen is 24.552 grams.

Learn more about ideal gas law:

Answer:

A polar covalent bond is a covalent bond in which the atoms have an unequal attraction for electrons and so the sharing is unequal. In a polar covalent bond, sometimes simply called a polar bond, the distribution of electrons around the molecule is no longer symmetrical.

Explanation:

Answer : it has been tested

Explanation:

i took the test

Hydrogen  bonding interaction occurs between  the oxygen atom of water and  the hydrogen atom of allyl alcohol that is covalently bonded to the oxygen atom.

We must recall that allyl alcohol is a molecular substance. Molecular substances do not dissociate into ions in water. As such particles of allyl alcohol remain intact when dissolved in water.

Hydrogen bonding occurs when hydrogen is bonded to an electronegative atom such as oxygen. In allyl alcohol, hydrogen  bonding interaction occurs between  the hydrogen atom of water and the oxygen atom of allyl alcohol.

Also,  hydrogen  bonding interaction occurs between  the oxygen atom of water and  the hydrogen atom of allyl alcohol that is covalently bonded to the oxygen atom.

Learn more: https://brainly.com/question/865531

Answer:

look at the explanation

Explanation:

Tides would be much higher also A lunar month would be about 10 days rather than 29 days, so the phases of the moon would go much quicker.

Answer: Metals are an excellent conductor of electricity and heat because the atoms in the metals form a matrix through which outer electrons can move freely.

Explanation:

Answer:

B

Explanation:

The rock is physically weathered down and decreases in size.

Answer:

I'm pretty sure its just the mass of the sample divided by the molar mass

for example if I had like 7g of carbon and wanted to find the moles, I would divide the mass I have (7g) by the molar mass (the atomic mass value on your periodic table, in this case for carbon it would be 14g)

moles = [tex]\frac{mass}{molarmass} = \frac{7}{14} = 0.5\ moles[/tex]

Hope this helped

Answer: 20 , 40

I want know the answer now !

Answer:

D: a heterogeneous mixture with components of varying sizes

Heterogeneous mixture is a combination of substances that doesn't have uniform composition and properties. Just by looking at the mixture you can differentiate the compounds because they are so different. Using a sieve, allows the components with different sizes to separate, while one is retained, the others can pass the holes in the sieve.

Explanation:

Answer: D, a heterogeneous mixture with components of varying sizes.

Heterogeneous mixture is a combination of substances that doesn't have uniform composition and properties. Just by looking at the mixture you can differentiate the compounds because they are so different. Using a sieve, allows the components with different sizes to separate, while one is retained, the others can pass the holes in the sieve.

Answer: i did the ones i knew

1. thorns

2. smell

6. long roots

8. smell

9. thorns

Explanation:

Answer:

Time of earthquake, magnitude and velocity, and type of seismic waves

Explanation:

Seismometers allow us to detect and measure earthquakes by converting vibrations due to seismic waves into electrical signals, which we can then display as seismograms on a computer screen. Seismologists study earthquakes and can use this data to determine where and how big a particular earthquake is.

Answer:

Solid and does not conduct electricity

Explanation:

This question is describing a thoroughly opened statement about the length of a three as 18 meters, which in the context of science can be referred to:

- A hypothesis or a result in the scientific method, if one is measuring the length of given objects.

- A measurement, if one is measuring the length of a three or any other object.

In both cases, we can note that the measurement has the following basic structure:

1. A number, defining how large or small the measurement is.

2. A unit, defining the system in which the measurement is reported to the scientific community.

Learn more:

Answer:

then this picture 11 Venkat and one person is

Explanation:

join date 20th December is not a problem with the topic of your name and address of the topic of your name and address of the topic of your name and address of the topic of your life in general is not available in the equation is the topic of your name and address

so nothing in this picture .

Answer:

It will take 22920 years to decay 112.5 g of 120 grams.

Explanation:

Explanation:

Flipping a light switch to turn on a light means that the circuit with the light is being closed. When the switch is flipped the opposite way, to turn the light off, the circuit is being opened.

Answer:

You now have an open circuit

Explanation:

The circuit is closed when the switch is flipped the other way to turn off the light.

Answer:

Explanation:

Since the whole magnet is magnetized, when you break a magnet in two parts, you will receive 2 mini magnets which will work just like a magnet.

Hoped this helped.

[tex]BrainiacUser1357[/tex]

Answer:

4

The two pieces would each have a north and south end

Answer:

Power Plant = Mitochondria (Mitochondria is the powerhouse of the cell)

City Limits = Cell Membrane (Outer layer of a cell)

City Hall = Nucleus (The nucleus is the control center in a cell)

City Food Processing Plant (Chloroplast process the cells food)

City Plans = Chromosomes (They contain the genetic information about the cell)

Community = Cytoplasm (Mainly process of elimination)

Explanation:

Explanations are in parenthesis

Answer:

Lustrous

Explanation:

Metals are lustrous which gives them a property of having Shiny surfaces

The valence electrons of metals jump easily to a higher energy orbital when light shines on them then they all fall emitting the excess energy as light show lustrous  property of metals.

Valence electrons are defined as a negatively charged particle that can be shared or transmitted between atoms that is found in the outermost shell of an atom. Valence electrons have a crucial role in determining how an atom will behave. The electrical configurations of elements can be used to find valence electrons. The total number of valence electrons in that element is then determined by counting the number of electrons in the outermost shell.

When newly treated, polished, or broken, a material takes on a bright look and conducts electricity and heat reasonably well. Metals are typically ductile and malleable. These traits are the result of the metallic bond that connects the atoms or molecules of the metal.

Thus, the valence electrons of metals jump easily to a higher energy orbital when light shines on them then they all fall emitting the excess energy as light show lustrous  property of metals.

To learn more about valence electrons, refer to the link below:

https://brainly.com/question/13993867

#SPJ2

Answer:

RBCs are disc-shaped with a flatter, concave center. This biconcave shape allows the cells to flow smoothly through the narrowest blood vessels. ... Many RBCs are wider than capillaries, but their shape provides the needed flexibility to squeeze through

Answer:

see below

Explanation:

1. 1 mol Mg = 24.31 g = 6.02 *10^23 atoms

     calculate the number of atomsin 80.45g Mg

         Numberof atoms = 6.02*10^23 Mg atoms / 24.31 g * 80.45 g

                                    = 1.99*10^24 atoms

2.1 mol C-12 = 12.01g = 6.02 * 10^23 atoms

    calculate the mass using

                                       = 12.01 g C / 6.02*10^23 atoms * 100 atoms

                                       = 1.99 * 10^-21 g

Answer:

1.9926 * 10 ^24 

Explanation:

Molar Mass - Use Periodic table!

M ( Mg ) = 24.31 g / mole

n = 80.45 g : 24.31 g/mole = 3.31 moles

N a ( Avogadro`s constant ) = 6.02 * 10 ^23

N = Na * n = 6.02 * 10 ^24 * 3.31 = 19.926 * 10 ^23

Answer:

no

Explanation:

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