2 Na (s) + Cl2 (g) → 2 NaCl (s) is an example of a physical or chemical change?

Answers

Answer 1

Answer:

Chemical change.

Explanation:

Physical Change                                                                                              

The changes that occur only due to change in shape or physical properties but their chemical or internal composition remain unchanged.  

Example :

Water converting to Ice

Water converting to gas

In this water molecule remain the same only they rearrange themselves that change its state of mater not composition

Chemical change:

The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.

These changes are irreversible

These changes occur due to chemical reactions  

These may not be observed with naked eye

Example:

Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood

The reaction of between sodium and chlorine:

2Na(s) + Cl₂(g) -------------------------------------> 2NaCl(s)


Related Questions

help me please !! is it A,B,C, or D ???

Answers

Ok, after doing an immense amount of research I came up with the most logical answer.

A. Is indicated by a negative enthrall sign.

Reasoning: an endothermic reaction is ice melting and the energy being more than its surroundings. Not specified to ice but as an example, ice is endothermic. That puts d and b out of the running leaving you left with a and c.

When I searched up enthalpy, it said “When a substance changes at constant pressure, enthalpy tells how much heat and work was added or removed from the substance.” Which is similar to c, right? Yeah, meaning both a and c are similar in that aspect.

The reason I decided to go with a is because heat is NOT released into the surrounding, exothermic reactions release energy and heat into the surrounding.

i need this ASAP i will give brainliest :)



Which term is defined as the ratio of the speed of light in a vacuum to the speed of light in the material it is passing through?

Answers

Answer:

I really dont know i just guessed :(

Explanation:

Answer:

index of refraction

Explanation:

What is another name for energy lost through heat and sound?

Answers

Answer:Figure 1. Energy losses in an incandescent light bulb are very large; most of the input energy is lost in the form of heat energy. This means that when energy is converted to a different form, some of the input energy is turned into a highly disordered form of energy, like heat. ...

Explanation:

Wilting is another name for losing energy

What is the correct name for the compound Li2S

Answers

Answer:

Lithium sulfide

What is better Music,Cartoons,Games,Anime,Knowledge Or Relaxation.

Answers

Answer:

anime

Explanation:

Games are the best to play

The half-life of carbon-14 is about ____________ years.

Fill in the blank.

Answers

The half-life of carbon-14 is about 5730 years

Answer:

5730 years

Explanation: for more on radiocarbon dating.) and hence explain why the amount of carbon-14 in the sample decays by half over any period of 5730 years.

Question 4 of 33
C
Q-Science-Gr7-SQSA1-CBT (2020-21)
Question: 1-4
Dead sean animals fall to the bottom of the ocean. A scientist notices rock layers that have formed on the ocean bottom with fossils of some of these animals. What type of rock

1.Lava
2.igneous
3.sedimentary
4.metamorphic

Answers

Answer:

The answer is Sedimentary

Explanation:

Thank you so much if that helps you!!!!

A student wants to investigate competition between two organisms. For the investigation, it
is most important that the student should choose organisms that
O require the same resources.
O reproduce at the same rate.
O are both active during the day.
o have the same adaptations.

(help please!!! due today!!!)

Answers

Answer:

i think that the answer is B

Explanation:

If a student wants to investigate competition between two organisms in an ecosystem the organisms should have same adaptations and use same resources.

What is an ecosystem?

Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.

Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.

Learn more about ecosystem,here:

https://brainly.com/question/1061425

#SPJ2

What represents a community?
pond
B
a snail
snails
D snails, guppies and plants

Answers

D snails, guppies and plants. The community should be diverse and have lots of biodiversity.

Answer:

to

Explanation:

to

What is the wavelength of a light wave that has a frequency of 4.42 x 10^14 Hz?

Answers

Answer:4.42×10

​14

​​ x

Explanation:

2. Which sentence explains how air pollution is harmful? *
(1 Point)
"When acid rain falls into rivers and lakes, many organisms in these habitats cannot survive
"fossil fuels, including oil. coal, and natural gas are our main sources of energy"
O to protect our planet in the future, we must make responsible decisions today"
Qption

Answers

Answer:Air Pollution is when gas and fuel is released into the air and damages the environment. The Answer out of your answers would be C.

Explanation:

How many different sublevels are in the third energy level?
A.3
B.4
C.1
D.2
the answer is a

Answers

Answer:

Its a

Explanation:

I got that answer on my own not from the Question ;)

One s-orbital is present in each sublevel of the primary energy level. There are 2 electrons in the s-orbital in total. When compared to other primary energy levels, the electrons in this orbital, known as s electrons, have the lowest energy. Here the correct option is A.

The fixed distances from an atom's nucleus where electrons may be found are referred to as energy levels (also known as electron shells). In an atom, the small, positively charged nucleus is surrounded by smaller, negatively charged electrons.

One s-orbital, three sets of p-orbitals, and five sets of d-orbitals make up the subshell of the third main energy level. S-orbitals can store a maximum of two electrons, p-orbitals six, and d-orbitals ten. One s-orbital is present in each sublevel of the primary energy level. There are 2 electrons in the s-orbital in total.

Thus the correct option is A.

To know more about energy level, visit;

https://brainly.com/question/9449510

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what is soluminescence? How does it work?​

Answers

Answer:

Sonoluminescence can occur when a sound wave of sufficient intensity induces a gaseous cavity within a liquid to collapse quickly. [...] The bubbles are very small when they emit the light—about 1 micrometer in diameter—depending on the ambient fluid (e.g., water) and the gas content of the bubble (e.g., atmospheric air).

Explanation:

Source is Google


3. What is the electron configuration of the following elements?
Lithium
Calcium
Copper
Strontium
Potassium
sodium

Answers

Answer: Lithium ( 3),Calcium (20),Copper (29),Strontium (38),Potassium (19),Sodium (11)

Explanation:

Please help... awarding 20 points and brainiest if correct.

Answers

Answer:

CH4

- 4 electron

- 0 electron

- the geometry of Ch4 is tetrahedral

AlF3

- 3 electron

- 0 electron

- the geometry is trigonal planar

CCl4

- 4 electron

- 0 electron

- the geomotry is tetrahedral

SeH2

- 2 electron

- 2 electron

- the geometry is V shape

What is the second life cycle stage during complete metamorphosis of insects?

O A) The eggs hatch into larvae.

OB) The eggs hatch into nymphs.

OC) Nymphs stop molting and are adult sized.

OD) Larvae make hard, protective cases around themselves during the pupal stage.​

Answers

Answer:

They hatch into larvae.

Explanation:

20 mL of a gas at 200K is heated until the new volume is 55 mL. What is the final temperature of the gas?

answer options:
4.0 K
5.5 K
400K
550 K

Answers

Answer:

550 K

Explanation:

Given the following data;

Original Volume, V1 = 20mL

Original Temperature, T1 = 200K

New Temperature, V2 = 55mL

To find new temperature T2, we would use Charles' law.

Charles states that when the pressure of an ideal gas is kept constant, the volume of the gas is directly proportional to the absolute temperature of the gas.

Mathematically, Charles is given by;

[tex] VT = K[/tex]

[tex] \frac{V1}{T1} = \frac{V2}{T2}[/tex]

Making T2 the subject of formula, we have;

[tex]T_{2} = \frac{V2}{V1} * T_{1}\\[/tex]

Substituting into the equation;

[tex]T_{2} = \frac{55}{20} * 200\\T_{2} = \frac{11000}{20}\\T_{2} = 550K[/tex]

Therefore, the new temperature is 550K.

The radioactive isotope used in the dating of fossils thought to be less than 40,000 years old is ________________.

Fill in the blank.

Answers

Answer:

The answer is Radiocarbon

1. Which best represents a compound?

Answers

Answer:

D

Explanation:

The one that best represents a compound is answer "D" because you compounds are chemically bonded and are always together.

Can radiation take place in solids, liquids, and gasses?

Answers

                  Hey Emma Here!

Answer:

Yes!

Explanation:

Liquids & gases are poor conductors, but they can make heat (thermal energy) travel quickly from one point to another. ... ~ When waves of heat (thermal energy) travel through empty space and transparent mediums, heat transfer by radiation occurs. Solids, liquids, & gases can all be heated by radiation.

Bye Have A Nice Day!

Explain What is an elementary reaction and how is it related to a reaction mechanism

Answers

Answer:

The sequence of individual steps, or elementary reactions, by which reactants are converted into products during the course of a reaction is called the reaction mechanism. The overall rate of a reaction is determined by the rate of the slowest step, called the rate-determining step.

Explanation:

help it's chemistry ​

Answers

Answer:

wavelength = wave velocity/frequency.

Explanation:

c

 is a constant. It is usually given as

3.00

×

10

8

m/s or

3.00

×

10

10

cm/s rounded to three significant figures.

Wavelength is measured in meters, centimeters, nanometers, etc...).

Frequency has a unit of

1/s

which means

1

cycle per second. It is also given the unit Hertz (Hz) in honor of German physicist Heinrich Hertz who proved the existence of electromagnetic waves.

1

Hz

=

1/s

.

14. How long does it take to travel a distance of 672 km at a speed of 96
km/hr?
0.14 hours
64, 512 hours
7 hours
10 hours

Answers

Answer:

7 hours

Explanation:

627/96=7

7

I hope this helped! :)

Can someone please help me by answering this question??

Answers

Answer: 12N IT IS JUST MATH

Explain what makes a cirrus cloud.

Answers

Answer:

the answer is below

Explanation:

Cirrus clouds form from the ascent of dry air, making the small quantity of water vapour in the air undergo deposition into ice (to change from a gas directly into a solid). Cirrus is made up completely of ice crystals, which provides their white colour and form in a wide range of shapes and sizes.

What is the specific heat of a substance that absorbs 1000 joules of heat when a sample of 25 g of the substance increases in temperature from 10.0C to 60.0C

Answers

Answer:

1250000

Explanation:

Specific heat is mass times specific heat capacity times change in temperature to get chance in temperature minus the old temperature from the new temperature then complete equation hence 25g×1000j×(60-10)

25g×1000j×50

=1250000g/j/degree Celsius

1375 J of heat energy are added to a 50.0 g sample of copper, which increases temperature from 22.8 C to 94.2 C. Calculate the specific heat of copper.

Answers

Answer:

0.385 J/g°C

Explanation:

Using the following formula, the specific heat of an elemental substance can be calculated:

Q = m × c × ∆T

Where;

Q = quantity of heat (J)

m = mass (g)

c = specific heat capacity (J/g°C)

∆T = change in temperature (°C)

Based on the given information, Q = 1375J, m = 50g, initial temperature = 22.8°C, final temperature = 94.2°C, c =?

Q = m × c × ∆T

1375 = 50 × c × (94.2 - 22.8°C)

1375 = 50 × c × 71.4

1375 = 3570c

c = 1375/3570

c = 0.3851

c = 0.385 J/g°C

Please answer fast!!!!!!!The table shows the distance that car 2 traveled during three trials. What is the average distance traveled by car 2 without a bumper? Be sure to show your work.


Trial 1 Trial 2 Trial 3

25, 27, 29

Answers

Answer: 25 + 27 + 29 = 81

81 divided by 3 = 27

your answer is 27

Explanation: you add them all together then however many numbers there are is how you divide it

Answer:

81 and 27 i think

Explanation:

What order do they go in plz someone help

Answers

Continental crust, oceanic crust, mantle , outer core , and inner core.
Oceanic crust, continental crust, mantle, the inner and outer core. Hope this helped and I hope it’s right!

Substances like neon , which is a gas at room temperature and pressure, can often be liquified or solidified only at very low temperatures. At a pressure of , does not condense to a liquid until and does not freeze until . What are the equivalent absolute temperatures?

Answers

Answer:

Condenses at 27.25K.

Freezes at 24.65K.

Explanation:

In order to solve this above question, there is is need to make use of the following equation. The main idea here is to convert degree celsius to Kelvin. Hence,

0°C + 273.15 = 273.15K---------------------(1).

Therefore, we will make use of the above equation (1) and slot in the values for at degree celsius at which it condenses and at degree celsius at which it freezes.

So, we have at temperature at which it condenses:

-245.9°C + 273.15 = 27.25K.

Also, we have at temperature at which it freezes.

-248.5°C + 273.15 = 24.65K.

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