Answer: Human activities have affected more than D). 70 percent of the Earth's surface
Explanation:
Final answer:
Human activities have transformed over 50% of the Earth's surface, including significant land use changes and impacts on the climate due to emissions from burning fossil fuels.
Explanation:
Human activities have affected more than 50 percent of the Earth's surface. Humans have transformed a large portion of the Earth's land through the expansion of cropland and pasturelands, reduction of forest habitats, and acceleration in land conversion for agriculture and habitation. Human influence extends beyond the land to the oceans and atmosphere through practices like burning fossil fuels, which has contributed substantially to climate change.
Jordan needs to repeat the experiment but his teacher says that he needs to improve his design in his second experiment what should he do different
Jordan has to include control factors including light, temperature, and nutrient levels to improve the experiment's design. He must make sure that, aside from the music exposure, the second experiment's parameters are the same for both plants.
Jordan should continue to maintain control over variables that might affect tomato development in the revised experiment. To ensure that any variations in tomato yield are mostly attributable to the music's effect, controllable variables such as light intensity, temperature, and nutrient delivery must be present.
With the exception of the music exposure, both plants should be put to the same conditions. This well designed setup will make it easier to pinpoint the precise impact of music on tomato development.
Additionally, a larger sample size with both tomato plants exposed to music and those not will yield more reliable results. Jordan will be able to make more trustworthy deductions regarding the real effects of music on plant growth in this way.
To know more about control factors here https://brainly.com/question/26146814
#SPJ3
The given question is incomplete, complete question is- "Jordan is doing a science fair project on the effects of music on the growth of tomatoes. He has two tomato plants, Plant A and Plant B, that he grows in a window and gives the same amount of water. Plant A is exposed to classical music using headphones attached to the soil. Throughout the growth period, Jordan counts the number of tomatoes produced by each plant.
Plant A = 35 Tomatoes | Plant B = 55 Tomatoes
Jordan needs to repeat the experiment but his teacher says that he needs to improve his design in his second experiment what should he do different?"
Why is liquid silver less dense than solid silver
Answer:
The same mass divided by a larger volume results in a smaller value for density. Therefore, liquid silver is less dense than solid silver. Temperature and solid density The density of solids usually decreases slightly as temperature increases because solids expand when heated.
Explanation:
Hope this helps
-A Helping Friend (mark brainliest pls)
Liquid silver is less dense than solid silver due to the density between these two species.
Density:It is defined as the ratio of mass over volume. The same mass divided by a larger volume results in a smaller value for density. Therefore, liquid silver is less dense than solid silver. The density of solids usually decreases slightly as temperature increases because solids expand when heated. The vibrations of the molecules increases, and it is easier for the molecules to slide past each other.
Find more information about Density here:
brainly.com/question/6838128
PLEASE ANSWER
In electromagnetic waves High Frequency = _______________.
A. high energy
B. low energy
C. long wavelengths
D. high amplitude
Answer:
option A
Explanation:
Electromagnetic waves are those waves which is produced by oscillation or vibration between the magnetic field and electric field. For example radio waves, visible radiation, ultraviolet, infrared, microwaves etc
In electromagnetic waves higher the frequency means higher the energies and higher the energy means lower the wavelength.
Like gamma rays have highest frequencies with highest energy and shortest wavelength.
because the light rays never meet, a concave lens can produce
Answer:
Virtual images.
Hope this helps.
5)
A chlorine atom reacts with a sodium atom to form sodium chloride, NaCl. A chlorine atom can also react with another chlorine atom to form a chlorine molecule, Cl2. Which statement BEST explains the behavior of chlorine in these two reactions
Answer:
C
Explanation:
Answer: option C
Explanation:
A chlorine atom can form ionic bonds by accepting an electron and covalent bonds by sharing electrons
How many grams of zinc would be required to produce 9.65g of zinc hydroxide
The question is incomplete, here is the complete question:
How many grams of zinc would be required to produce 9.65g of zinc hydroxide
Zn+2MnO₂+H₂O→Zn(OH)₂+Mn₂O₃
Answer: The mass of zinc required is 6.35 grams
Explanation:
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] .....(1)
Given mass of zinc hydroxide = 9.65 g
Molar mass of zinc hydroxide = 99.4 g/mol
Putting values in equation 1, we get:
[tex]\text{Moles of zinc hydroxide}=\frac{9.65g}{99.4g/mol}=0.0971mol[/tex]
The given chemical equation follows:
[tex]Zn+2MnO_2+H_2O\rightarrow Zn(OH)_2+Mn_2O_3[/tex]
By Stoichiometry of the reaction:
1 mole of zinc hydroxide is produced from 1 mole of zinc
So, 0.0971 moles of zinc hydroxide will be produced from = [tex]\frac{1}{1}\times 0.0971=0.0971mol[/tex] of zinc
Now, calculating the mass of zinc from equation 1, we get:
Molar mass of zinc = 65.4 g/mol
Moles of zinc = 0.0971 moles
Putting values in equation 1, we get:
[tex]0.0971mol=\frac{\text{Mass of zinc}}{65.4g/mol}\\\\\text{Mass of zinc}=(0.0971mol\times 65.4g/mol)=6.35g[/tex]
Hence, the mass of zinc required is 6.35 grams
Fe + _ H2SO4 _ Fe2(SO4)3 + _ H2
2.50g of a certain Compound X, known to be made of carbon, hydrogen and perhaps oxygen, and to have a molecular molar mass of 128. g/mol, is burned completely in excess oxygen, and the mass of the products carefully measured:
product mass
carbon dioxide 8.60g
water 1.41g
Use this information to find the molecular formula of X.
The molecular formula of the compound is C4H8O4.
Explanation:The molecular formula of Compound X can be determined by calculating the empirical formula and then obtaining the molecular formula based on the molar mass. First, we calculate the empirical formula using the mass percentages of carbon, hydrogen, and oxygen in the compound. From the given information, the empirical formula is CH2O. To obtain the molecular formula, we need to calculate the empirical formula mass by summing the atomic masses of its elements. The empirical formula mass of CH2O is 30.03 g/mol. To find the molecular formula, we divide the molecular molar mass (128 g/mol) by the empirical formula mass (30.03 g/mol). The result is approximately 4.27, which indicates that the molecular formula of Compound X is 4.27 times the empirical formula. Multiplying the subscripts of the empirical formula (CH2O) by 4.27, we get the molecular formula of Compound X as C4H8O4.
Learn more about Molecular formula here:https://brainly.com/question/36480214
#SPJ3
.92 moles of carbon dioxide, CO2, was produced when you burned C6H120. (glucose) with O2.
How many grams of water was also produced?
CGH 120(s) + 6 O2(g) – 6 CO2 (g) + 6 H20 (8)
O moles to moles
moles to mass
mass to moles
mass to mass
Answer:
16.56g.
Explanation:
You need to compare the number of coefficient of the reaction product to find how much water produced. The reaction formula will produce 6 carbon dioxide(CO2) and 6 water (H2O).
If the reaction produces 0.92 moles of carbon dioxide, then the amount of water produced in moles will be: 0.92 moles * (6/6)= 0.92 moles
The molar mass of water is 18g/mol, so the calculation of moles to mass will be: 0.92 moles * (18g/mol)= 16.56g.
What happens during a phase change from a solid to a liquid?
1.The particles the solid vibrate faster and faster. After a while, they stop all motion.
2.The particles of the solid vibrate slower and slower. After a while, they stop moving.
3.The particles of the solid vibrate faster and faster. After a while, they can start to move around.
4.The particles of the solid vibrate slower and slower. After a while, they can start to move around.
Answer:
The particles of the solid vibrate faster and faster. After a while, they can start to move around
Explanation: Solid particles movement are restricted due to the strong force of attraction between the molecules,Solid phase will only change to liquid phase if the forces of attraction holding the molecules together are broken down by heat, when this happens the solid particles movement will become more mobile as the substance is moving from solid phase and liquid phase
Which phrase best describes the main reason scientist perform experiments
Answer: an experiment is an empirical procedure that arbitrates competing models or hypotheses. Researchers also use experimentation to test existing theories or new hypotheses to support or disprove them.
Explanation: I don't know if this helps but if it does let me know.
Final answer:
Scientists perform experiments primarily to test hypotheses, gather data, and validate or disprove their proposed explanations for phenomena. These experiments are essential for the advancement of scientific knowledge and are often peer-reviewed and published if the results are significant.
Explanation:
The main reason scientists perform experiments is to test a hypothesis which is a proposed explanation for a phenomenon, and to answer specific research questions. Experiments are carefully designed to collect data and analyze results objectively. If the results support the hypothesis, further experiments may be conducted to test related hypotheses, or if the results are inconsistent with the hypothesis, it may be discarded for a new alternative hypothesis.
By performing experiments, scientists aim to ensure repeatability and to explore underlying causes for observed phenomena. Experiments are a critical aspect of the scientific method, enabling researchers to extend their knowledge of the natural universe through empirical evidence. The design of an experiment is guided by the goal to make measurements that test the hypothesis, and often involves statistical, mathematical, or graphical analysis of the data collected.
Significant results get published in scientific journals, which serve to communicate the findings and contribute to the body of scientific knowledge. With the advent of open access and electronic journal availability, the dissemination of scientific knowledge has become more accessible.
How do water molecules dissolve a salt?
O
A. The water molecules move around the salt crystals.
O
B. The water molecules separate the crystals into molecules.
O
C. The water molecules move around the salt ions.
D. The salt crystals squeeze in between water molecules.
The correct answer is B) The water molecules separate the crystals into molecules.
What's a molecule?The smallest particle of a substance that has all of the physical and chemical properties of that substance. Molecules are made up of one or greater atoms.
What are the kinds of molecules?Diatomic Molecules -- A diatomic atom consists of the most effective atoms, of equal or distinctive chemical factors. Heteronuclear Diatomic Molecules -- A heteronuclear diatomic molecule consists of atoms of equal detail mixed. OXYGEN MOLECULE.CARBON MONOXIDE MOLECULE (CO)How does water dissolve salt?
Water dissolves in salt because the terrible part of a water molecule, the oxygen part is interested in the wonderful sodium ion of the salt. also, the effective part of the water molecule, the hydrogen component is drawn to the terrible chloride ion of the salt. Water molecules pull the sodium and chloride ions aside, breaking the ionic bond that held them together. After the salt compounds are pulled apart, the sodium and chloride atoms are surrounded via water molecules. once this occurs, the salt is dissolved, ensuing in a homogeneous solution.
Learn more about molecules here: https://brainly.com/question/26044300
#SPJ2
Answer:
it’s C
Explanation:
How many liters are in a .00813M solution that contains 1.55 g of KBr?
Answer:
1.602 L (or) 1602 mL
Explanation:
Molarity is the amount of solute dissolved per unit volume of solution. It is expressed as,
Molarity = Moles / Volume of Solution ----- (1)
Rearranging above equation for volume,
Volume of solution = Moles / Molarity -------(2)
Data Given;
Molarity = 0.00813 mol.L⁻¹
Mass = 1.55 g
First calculate Moles for given mass as,
Moles = Mass / M.mass
Moles = 1.55 g / 119.002 g.mol⁻¹
Moles = 0.0130 mol
Now, putting value of Moles and Molarity in eq. 2,
Volume of solution = 0.0130 mol / 0.00813 mol.L⁻¹
Volume of solution = 1.60 L
or,
Volume of solution = 1602 mL
a 4.0 L sample of gas at 1.4 atm is heated from 298ck to 310 k. the pressure of the gas increases to 2.1 atm. what is the new volume of the gas ?
Answer:
3.5
Explanation:
The gas in the reaction is considered as the ideal gas. The new volume of the gas with heating was 2.77 L.
What is an ideal gas law?The ideal gas law can be given as:
[tex]PV=nRT[/tex]
For a gas with the change in pressure and temperature, the change in volume is given as:
[tex]\dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}[/tex]
Substituting the initial pressure ([tex]P_1[/tex]), initial volume ([tex]V_1[/tex]), initial temperature ([tex]T_1[/tex]), final pressure ([tex]P_1[/tex]) final temperature ([tex]T_2[/tex]), and the final volume ([tex]V_2[/tex]) can be given as;
[tex]\rm \dfrac{1.4\;atm\;\times\;4\;L}{298\;K} = \dfrac{2.1\;atm\;\times\;\textit V_2}{310\;K}\\\\ \textit V_2=2.77\;L[/tex]
The new volume of the gas is 2.77 L.
Learn more about ideal gas, here:
https://brainly.com/question/8711877
5. Using the terms: metal and nonmetal, describe what types of atoms make up each type of
bond.
Answer:
See the answer below, please.
Explanation:
The bonds formed between metals and nonmetals are called ionics. These occur between atoms with electronegativity difference. Example: NaCl (Sodium Chloride)
Instead, covalent bonds are formed between two nonmetals (one or more electron pairs are shared). Example: H202 (hydrogen peroxide).
In the case of metal formed bonds, they are called metallic.
How many moles of oxygen are needed to react with 23.8 moles of aluminum?
Answer:
17.85moles
Explanation:
Check attachment
which sequence of coefficients should be placed in the blanks to balance this equation
Answer:
2 ... and 1
Explanation:
Hope this is right / helps
Answer:
It could either be 1 or 2. Depending on the question.
Explanation:
what is bromine classified as?
Answer:
The chemical element bromine is classed as a halogen and a nonmetal.
Explanation:
Which of the following could a magnet float over?
A. A network solid
B. A molecular solid
C. A semiconductor
D. A superconductor
As the ions present on a magnet and a superconductor are oppositely charged, it would help a superconductor to float over a magnet.
What are ions?An ion is defined as an atom or a molecule which has a net electrical charge. There are 2 types of ions :1) cation 2) anion . The cation is the positively charged ion and anion is the negatively charged ion . As they are oppositely charged they attract each resulting in the formation of ionic bond.
Ions consisting of single atom are mono-atomic ions while which consists of two or more ions are called as poly-atomic ions . They are created by chemical interactions . They are very reactive in their gaseous state and rapidly react with oppositely charged ions resulting in neutral molecules.Ions of opposite charges attract in an ionic bond.
Learn more about ions,here:
https://brainly.com/question/29183072
#SPJ5
How do the physical and chemical properties of the element change?
Physical properties of a substance are measured without changing its composition. Chemical properties describe a substance's potential for chemical change.
Physical and chemical properties are key concepts in understanding how substances interact with one another and change. Physical properties, such as hardness, boiling point, and mass, describe the physical characteristics of a substance without altering its chemical composition. They can be observed or measured during physical changes, which include states of matter like melting, freezing, and vaporisation, where no new substance is formed.
In contrast, chemical properties describe a substance's ability to undergo changes that alter its chemical structure, like flammability or acidity. Chemical changes result in the formation of one or more new substances with different properties, a process where chemical bonds are broken or formed. For example, when carbon burns in oxygen, it forms carbon dioxide, indicating a chemical change from the original substances.
which diagram best illustrates the ion-molecule attractions that occur wen the ions NaCl(s) are added to water
The correct image is option A
What happens when we add NaCl to water?
The process of dissolving table salt (NaCl) in water is known as dissolution. The salt separates into sodium (Na⁺) and chloride (Cl⁻) ions, which are its component ions. These ions, which are charged positively or negatively, interact with the molecules of water to surround and disseminate themselves.
A homogenous mixture known as saltwater is created as a result. The ionic connections holding the salt crystal lattice together are broken during the physical process of NaCl dissolving in water, distributing the ions uniformly throughout the solution.
The diagram that best ilustrates the ion-molecule attractions that occur when the ions of NaCl(s) are added to water is option B)
When sodium chloride (NaCl) is added to water, it dissolves and dissociates into Na+ and Cl- ions. These ions are then surrounded by water molecules due to ion-dipole attractions. Water molecules are polar, with a partially negative oxygen atom and partially positive hydrogen atoms.
The positive sodium ions are attracted to the negative oxygen atoms in the water molecules, and the negative chloride ions are attracted to the positive hydrogen atoms. This results in the formation of a hydrated lattice, where the ions are surrounded by water molecules.
In this experiment, you will change the temperature and particle size of the antacid tablet and observe how these changes affect reaction. In the space below, write a scientific question that you answered by doing this experiment
Answer:
They change the rate of reaction.
Explanation:
Temperature increases the rate of reaction as particles move faster.
(Temperature is the average kinetic energy of particles)
Reducing the particle size increases the surface area to volume ratio, which increases the rate of reaction.
Answer:
Format: What are the effects of X and Y on Z?
Independent variable 1: temperature
Independent variable 2: particle size
Dependent variable: reaction rate
Explanation:
i just answered it on e2020
What are the four main reservoirs of carbon
the atmosphere,the terrestrial biosphere, the oceans and the sediments
How many electrons can copper lend?
Final answer:
Copper can lend one or two electrons per atom in chemical reactions, commonly two for the reduction of Cu²⁺ ions, and has free conduction electrons that make it an excellent electrical conductor.
Explanation:
Copper can lend different numbers of electrons depending on the chemical process involved. For instance, in a redox reaction where copper ions are being reduced, two electrons are typically required to reduce a single Cu²⁺ ion to metallic copper (Cu). Since the atomic structure of copper allows for an outermost electron to be loosely bound, copper can conduct electricity well due to the movement of these conduction electrons.
In a typical copper wire or sheet, there is one free electron per atom that can be transferred. However, the number of electrons a copper atom can lend is not unlimited; it is restricted by the reaction conditions and the valence of the copper involved in the reaction.
The law of conservation of mass tells us, in part, that matter is neither created nor destroyed.
How can the law of conservation of mass for a chemical reaction be expressed?
Law of conservation of mass for a chemical reaction can be expressed by all of the above.
What is law of conservation of mass?According to law of conservation of mass, it is evident that mass is neither created nor destroyed rather it is restored at the end of a chemical reaction .
Law of conservation of mass and energy are related as mass and energy are directly proportional which is indicated by the equation E=mc².Concept of conservation of mass is widely used in field of chemistry, fluid dynamics.
Law needs to be modified in accordance with laws of quantum mechanics under the principle of mass and energy equivalence.This law was proposed by Antoine Lavoisier in the year 1789.For a reaction to obey law of conservation of mass it must be balanced.
Learn more about law of conservation of mass,here:
https://brainly.com/question/28711001
#SPJ2
Your question is incomplete, but most probably your full question was,the law of conservation of mass tells us, in part, that matter is neither created nor destroyed.How can the law of conservation of mass for a chemical reaction be expressed? A. By using using coefficients coefficients in in a chemical equation B. By writing a a balanced balanced chemical equation C. By counting the atoms present on each side of the equation D. All of of the the above
The law of conservation of mass states that in a chemical reaction, matter is neither created nor destroyed, meaning the total mass of the reactants equals the total mass of the products. Introduced by Antoine Lavoisier in 1789, this principle highlights that matter can change forms but the total mass is conserved.
The law of conservation of mass states that matter is neither created nor destroyed during a chemical reaction. This means that the total mass of the reactants (substances that undergo the changes) must be equal to the total mass of the products (substances formed as a result of the reaction). For example, when burning charcoal in oxygen, the mass of the charcoal and oxygen before the reaction is the same as the mass of the carbon dioxide, water vapor, and ash produced. Antoine Lavoisier, a French chemist, introduced this concept in 1789, emphasizing that although matter can change forms (e.g., from a solid to a gas), the total mass remains constant before and after the reaction. The rearrangement of atoms during reactions ensures the conservation of mass.
2 Points
Which of the following is true of tetrads?
THERE
MENTELE
OS
DELETE
LE
SERIES
SEDER
O
A. They exist throughout the process of meiosis.
O
B. They separate during meiosis I.
EHEEEEE
SERIES
OLEH
CHILE
BENZ
HEER
UHERAPIE
meget
B
R
IS
HI
ELE
TEEN
IER
02
HERRERA
FERIE
ESTE
CD
ENTER
ESEBRER
C
S
BARTH
HARF
FREE FOR
FSHA
SEL
TERR
GENESIS
ES
S
FREE
O
C. They are found only in haploid cells.
O
D. They also form in cells undergoing mitosis.
THE NE
HE
FREE
ME
F
Answer:
four times im cool.
Explanation:
The following is true of tetrads is they separate during meiosis I.
The correct option is (B).
Tetrads, also known as bivalents, are structures formed during the prophase I stage of meiosis, specifically during the crossing over process. During prophase I, homologous chromosomes pair up to form tetrads. Each tetrad consists of two homologous chromosomes, each composed of two sister chromatids. This pairing allows for the exchange of genetic material between homologous chromosomes through crossing over.
Once tetrads are formed, they undergo a process called crossing over, where segments of DNA are exchanged between the paired homologous chromosomes. This genetic recombination increases genetic diversity among the resulting gametes.
During meiosis I, tetrads align at the metaphase plate, and then homologous chromosomes separate, with one chromosome from each homologous pair moving to opposite poles of the cell. This separation occurs during the first division of meiosis, known as meiosis I. Therefore, option B, "They separate during meiosis I," is the correct statement regarding tetrads.
As for the other options:
A. Tetrads do not exist throughout the process of meiosis. They are transient structures formed during prophase I and are resolved as homologous chromosomes separate during meiosis I.
C. Tetrads are not found only in haploid cells. They are formed during meiosis, which ultimately leads to the production of haploid cells (gametes), but they themselves are formed during the diploid stage of meiosis.
D. Tetrads do not form in cells undergoing mitosis. Mitosis involves the division of a diploid cell into two identical diploid daughter cells, and it does not involve the pairing of homologous chromosomes or the formation of tetrads. Tetrads are specific to meiosis, which is a process of cell division that leads to the formation of haploid gametes for sexual reproduction.
complete question given below:
Which of the following is true of tetrads?
A. They exist throughout the process of meiosis.
B. They separate during meiosis I.
C. They are found only in haploid cells.
D. They also form in cells undergoing mitosis.
Calculate the heat needed to change 3.00 * 10^2 grams of water at 25 degrees celsius to steam at 100 degrees celsius
Answer:
9.4×10⁴J
Explanation:
The specific heat capacity (SHC) of water, which is the amount of energy (J) that it takes to warm 1mL (1mL = 1g) of water by 1°C is 4.184 J/g×°C.
Q = mcΔT relates energy to mass, SHC, and change in temperature.
The mass of water is 300g, and will not change because no water will evaporate until it reaches 100°C.
The change in temperature is 75°C:
100°C - 25°C = 75°C
(Desired temp. - initial temp. = change in temp.)
Subbing these values into Q=mcΔT:
Q = 300g × 4.184J/g×°C × 75°C
Q = 94140J
Scientific notation tells us that we have two significant figures, so:
Q = 9.4 × 10⁴J
How do you do a stoichiometric problem
Write the balanced chemical equation.
Convert the units of the given substance (A) to moles.
Use the mole ratio to calculate the moles of wanted substance (B).
Convert moles of the wanted substance to the desired units.
Low air pressure can cause
Question 5 options:
clouds and precipitation to form
the temperature to drop
a sunny day
fog
Answer: clouds and precipitation to form
Explanation: In a low pressure system warm air rises into the atmosphere and cools down and forms cloud. In low air pressure the humidity is high since there is enough space for water vapor to occupy causing precipitation.
19. Which of the following best describes the role of the spark from the spark plug in an automobile engine?
(A) The spark decreases the energy of activation for the slow step.
(B) The spark increases the concentration of the volatile reactant.
(C) The spark supplies some of the energy of activation for the combustion reaction.
(D) The spark provides a more favorable activated complex for the combustion reaction.
(E) The spark provides the heat of vaporization for the volatile hydrocarbon.
The role of a spark plug is to supply some of the energy of activation for the combustion reaction.
Explanation:
A Spark plug is a tiny bolt of lightning in which a spark of electricity is emitted across a gap creating the ignition of the combustion chamber thereby starting the engine. By putting an engine piston in motion we can power up which produces a smooth burn of the compressed air-fuel mixture.An electrical device that fits into the cylinder head and ignites compressed aerosol gasoline by an electric spark. They have an insulated electrode connected to a coil that ignites thereby producing sparks.The spark plug works as a heat exchanger. They tend to pull unwanted thermal energy from the combustion chamber and heat is transferred to the engine's cooling system. Thus they supply some of the energy for the activation of engines.The correct answer is (C) The spark supplies some of the energy of activation for the combustion reaction, is best describes the role of the spark from the spark plug in an automobile engine.
In an automobile engine, the spark from the spark plug plays a crucial role in initiating the combustion process. The combustion reaction involves the rapid oxidation of a fuel, typically a volatile hydrocarbon, which releases a significant amount of energy. However, this reaction requires an initial input of energy to overcome the energy barrier known as the activation energy.
The spark from the spark plug provides this necessary energy of activation. When the spark plug ignites, it creates a small, high-energy spark that is hot enough to initiate the combustion of the air-fuel mixture in the engine's cylinder. This spark raises the temperature of a small portion of the fuel-air mixture to a point where the molecules have enough kinetic energy to react with each other, thus starting the combustion reaction.
Once the reaction starts, it releases enough energy to sustain itself and continue the combustion process without additional input from the spark plug. The energy released by the combustion reaction is what powers the engine by pushing the pistons down, which in turn rotates the crankshaft and ultimately drives the vehicle's wheels.
To summarize, the spark from the spark plug is essential because it:
- Provides the energy of activation needed to initiate the combustion reaction.
- Does not decrease the energy of activation (option A).
- Does not significantly increase the concentration of the volatile reactant (option B).
- Does not alter the activated complex (option D), as the activated complex is a theoretical state in the reaction pathway, not something that can be provided or altered by external means.
- Does not provide the heat of vaporization (option E) for the hydrocarbon, as the spark's role is to initiate combustion, not to vaporize the fuel, although vaporization of the fuel is a necessary step before combustion.
Therefore, the spark's role is to supply some of the energy of activation for the combustion reaction, making option (C) the correct description.