All categories

3 years ago

For each example of a phase change, identify whether heat is absorbed from the surroundings or

Chemistry

1 answer:

vladimir1956 [14]3 years ago

4 0

In case of popsicle and alcohol, heat is absorbed from the surrounding.

In case of lava heat is emitted into the surrounding.

<h3>Explanation:</h3>

Melting of popsicle is just a change of state from solid to liquid. This is the phenomenon which occurs when the popsicle gets the heat from the surrounding and it absorbs the heat, thereby turning into liquid. So it absorbs heat from the surrounding.

The alcohol when spread on the skin evaporates into vapour. This is the phenomenon of evaporation which occurs when alcohol absorbs heat from the surrounding and thereby turning into vapour.

Similarly, when lava solidifies into solid, the change of state occurs. As lava emits heat into the surrounding, the temperature of the lava goes down, thereby changing it into solid. So it emits heat into surrounding.

You might be interested in

Compounds Lab Report

lukranit [14]

Name and Title:

Colleen DeBruin, Hillary Mulkavits, 11/18/2020, compounds lab.

Objectives(s):

to build chemical compounds from known elements

Hypothesis:

if I use oxygen hydrogen and carbon then I can make five new compounds in four minutes

Procedure:

The materials and procedures are listed in your virtual lab. You do not need to repeat them here. However, you should note if you experienced any errors or other factors that might affect your outcome. Using your summary questions at the end of your virtual lab activity, please clearly define the dependent and independent variables of the experiment.

Data:

Record the composition of each of your compounds below. Be sure to include the number of atoms for each element. An example has been supplied for you.

Compound Name Chemical Formula Sodium (Na) Atoms Calcium (Ca) Atoms Hydrogen (H) Atoms Oxygen (O) Atoms Carbon (C) Atoms Chlorine (Cl) Atoms

Ex: Sodium

hypochlorite NaClO 1 0 0 1 0 1

Water H20 o 0 1 2 0 0

Glucose C6H12O6 0 0 12 6 6 0

Formic/methanoic acid HCOOH 0 0 2 2 1 0

Butanoic Acid C3H7COOH 0 0 8 2 4 0

Carbon Dioxide C02 0 0 0 2 1 0

Carbon Monoxide CO 0 0 0 1 1 0

Fructose C6H12O6 0 0 12 6 6 0

0 0 0

Conclusion:

Your conclusion will include a summary of the lab results and an interpretation of the results. Please answer all questions in complete sentences using your own words.

I found as many combinations of carbon hydrogen and oxygen as possible

If there is a job that combines elements you would be doing that every day making it an every day matter

elements are like people, they are all different causing them to react differently and be more reactive

H20 has four because there are 2 oxygen and one hydrogen because of the numbers in the name of the compound

Yes because two elements can form two different types of bonds causing different outcomes

If this isn't right I'm sorry but I had it as an assignment so we will get it wrong together lol

8 0

3 years ago

Read 2 more answers

A galvanic cell at a temperature of 42 degrees Celcius is powered by the following redox reaction:

seropon [69]

Answer: The cell voltage of the given reaction is 1.86 V

Explanation:

The given chemical equation follows:

$3Cu^{2+}(aq.)+2Al\rightarrow 2Al^{3+}(aq.)+2Au(s)$

Oxidation half reaction: $Al(aq.)\rightarrow Al^{3+}(aq.)+3e^-;E^o_{Al^{3+}/Al}=1.66V$ ( × 2)

Reduction half reaction: $Cu^{2+}(aq.)+2e^-\rightarrow Cu(s);E^o_{Cu^{2+}/Cu}=0.16V$ ( × 3)

Oxidation reaction occurs at anode and reduction reaction occurs at cathode.

To calculate the $E^o_{cell}$ of the reaction, we use the equation:

$E^o_{cell}=E^o_{cathode}-E^o_{anode}$

Putting values in above equation, we get:

$E^o_{cell}=0.16-(-1.66)=1.82V$

To calculate the EMF of the cell, we use the Nernst equation, which is:

$E_{cell}=E^o_{cell}-\frac{2.303RT}{nF}\log \frac{[Al^{3+}]^2}{[Cu^{2+}]^3}$

where,

$E_{cell}$ = electrode potential of the cell = ? V

$E^o_{cell}$ = standard electrode potential of the cell = +1.82 V

n = number of electrons exchanged = 2

R = Gas constant = 8.314 J/mol Kl

T = temperature = $42^oC=[42+273]K=315K$

F = Faraday's constant = 96500

$[Al^{3+}]=1.63M$

$[Cu^{2+}]=3.43M$

Putting values in above equation, we get:

$E_{cell}=1.82-\frac{2.303\times 8.314\times 315}{2\times 96500}\times \log(\frac{(1.63)^2}{(3.43)^3})\\\\E_{cell}=1.86V$

Hence, the cell voltage of the given reaction is 1.86 V

4 0

3 years ago

A type of chemical reaction in which an uncombined or free element replaces an element that is combined in a compound is called.

Leno4ka [110]

Answer:

C. Single displacement

Explanation:

3 0

2 years ago

Read 2 more answers

Elements in group 2 are all called alkaline earth metals. What is most similar about the alkaline earth metals?

german

Answer:

Explanation: the last one

4 0

3 years ago

Read 2 more answers

What are three physical properties of aluminum foil

timofeeve [1]

Aluminum foil is a metal so it has the typycal properties of metals. These are the three most representative properties of metals that aluminum foil exhibit:


1) It is good conductor of electricity: this property is consequence of the metallic bond, which permits that the outermost electrons of each atom can flow through the entire network of atoms conducting the electricity.


2) Is is good conductor of heat: this other property of metals is due to transmission of vibration that is carried out between neighboring atoms.


3) it is ductile: this property means that the metals can be formed into foils.


Other properties that can be mentioned are: solid at room temperature and mallealble (can form wires)

6 0

3 years ago