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
mixas84 [53]
2 years ago
11

Describe an example of an endothermic and exothermic reaction. For each of your reactions, identify whether it is a physical or

chemical change and explain how the reaction supports the law of conservation of mass.
Biology
2 answers:
Valentin [98]2 years ago
8 0

Answer:

he sum of the enthalpies of the reactants is greater than the products, the reaction will be exothermic.

Explanation:

Verdich [7]2 years ago
4 0

Answer:

Explanation:Endothermic reactions

Photosynthesis

Photosynthesis is the chemical reaction that takes place in green plants, which uses energy from the sun to change carbon dioxide and water into food that the plant needs to survive, and which other organisms (such as humans and other animals) can eat so that they too can survive. The equation for this reaction is:

6

CO

2

(g)

+

6

H

2

O (l)

+

energy

→

C

6

H

12

O

6

(s)

+

6

O

2

(g)

Photosynthesis is an endothermic reaction. Energy in the form of sunlight is absorbed during the reaction.

The thermal decomposition of limestone

In industry, the breakdown of limestone into quicklime and carbon dioxide is very important. Quicklime can be used to make steel from iron and also to neutralise soils that are too acid. However, the limestone must be heated in a kiln (oven) at a temperature of over

900

℃

before the decomposition reaction will take place. The equation for the reaction is shown below:

CaCO

3

(s)

→

CaO (s)

+

CO

2

(g)

Exothermic reactions

Combustion reactions

The burning of fuel is an example of a combustion reaction, and we as humans rely heavily on this process for our energy requirements. The following equations describe the combustion of a hydrocarbon such as petrol

(

C

8

H

18

)

:

fuel + oxygen

→

heat + water + carbon dioxide

2

C

8

H

18

(l)

+

25

O

2

(g)

→

16

CO

2

(g)

+

18

H

2

O (g)

+

heat

This is why we burn fuels (such as paraffin, coal, propane and butane) for energy, because the chemical changes that take place during the reaction release huge amounts of energy, which we then use for things like power and electricity. You should also note that carbon dioxide is produced during this reaction. The chemical reaction that takes place when fuels burn has both positive and negative consequences. Although we benefit from heat, power and electricity the carbon dioxide that is produced has a negative impact on the environment.

Respiration

Respiration is the chemical reaction that happens in our bodies to produce energy for our cells. The equation below describes what happens during this reaction:

C

6

H

12

O

6

(s)

+

6

O

2

(g)

→

6

CO

2

(g)

+

6

H

2

O

(l)

+

energy

In the reaction above, glucose (a type of carbohydrate in the food we eat) reacts with oxygen from the air that we breathe in, to form carbon dioxide (which we breathe out), water and energy. The energy that is produced allows the cell to carry out its functions efficiently. Can you see now why you must eat food to get energy? It is not the food itself that provides you with energy, but the exothermic reaction that takes place when compounds within the food react with the oxygen you have breathed in!

Fact:

Lightsticks or glowsticks are used by divers, campers, and for decoration and fun. A lightstick is a plastic tube with a glass vial inside it. To activate a lightstick, you bend the plastic stick, which breaks the glass vial. This allows the chemicals that are inside the glass to mix with the chemicals in the plastic tube. These two chemicals react and release energy. Another part of a lightstick is a fluorescent dye which changes this energy into light, causing the lightstick to glow! This is known as phosphorescence or chemiluminescence.

You might be interested in
A wave with a frequency of 0.5 Hz and a speed of 10 m/s has a wavelength of a. 50 m. c. 20 m. b. 0.5 m. d. 0.2 m. Please select
Blababa [14]
The correct option is c. (20 m) .
As the formula to calculate wavelength is :
wavelength = wavespeed / frequency
8 0
3 years ago
Ill give brainliest or wtv its called
BigorU [14]

Answer:

hi there!!

Explanation:

It is gaining water because it is growing.

4 0
2 years ago
The circulation of water in the ocean due to differences in density between the different layers of water is most likely respons
kolezko [41]
The circulation of water in the ocean due to differences in density between the different layers of water is most likely responsible for "<span>B deep water ocean currents" The moon is responsible for the tides, and under water volcanoes will erupt regardless of the water density.
</span>

7 0
3 years ago
Which nation would be CLOSEST to the command side on this economic
Alina [70]

Answer: D) North Korea

==============================================================

Explanation:

The United States, the United Kingdom, and France are all countries that have capitalistic economies. This means that (for the most part) private industry and the market determines what products are produced and who gets those products. I said "for the most part" because these countries don't follow a purely capitalistic structure. There are some elements of government regulation to ensure that no breakdowns occur. The regulations are also to ensure some level of fairness as well, in addition to preventing things like fraud.

On the other hand, countries like North Korea are known as command economies because the government determines what products are to be made and they determine who gets the products. This means that they set the prices as well to whatever they feel is correct (even if the market may disagree otherwise). The term "communism" is often strongly connected to the term "command economy".

7 0
3 years ago
What is the phenotype and the genotype of the white flowered offspring shown in the Punnet square below? Explain how you know by
scoundrel [369]

Answer:

Genotype: The letters that make up the individual. E.g. TT or Tt. ▪ Phenotype: The physical characteristics of the particular trait. E.g. Tall or short. ▪ Dominant trait: Signified by capital letter-E.g. T.

Explanation:

Hope this helps pls mark brainliest.

3 0
3 years ago
Other questions:
  • Which type of water is the most dense? A. cold water with high salt content B. warm, salty water C. cold water with low salt con
    9·1 answer
  • The fiber tracts indicated by the letter d will terminate in the __________. several examples of ascending spinal cord tracts. t
    9·1 answer
  • The process of transcription, which takes place in the nucleus of a cell, what is occurring?
    5·2 answers
  • Can anyone please help me on this at least some
    9·1 answer
  • Overfishing of (blank)
    8·1 answer
  • Oraciones con selva
    9·1 answer
  • You analyze a DNA sample and find that its base composition is 30% A, 20% T, 30% G, and 20% C. What can you conclude about the s
    9·1 answer
  • Consider the model for natural selection. Describe a scenario that represents this model of natural selection.
    11·2 answers
  • The brain is the main organ of the: circulatory system nervous system digestive system excretory system
    6·2 answers
  • As a result of a mutation, the DNA sequence AGT - TGA - CAT changes to AAT - TGA - CAT.
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!