Answer:
Option A: It is likely that more rock candy will be formed in batch A.
Explanation:
The difference between batch A and batch B is that batch A uses temperature to dissolve the sugar, while the dissolution of the sugar in batch B is produced at room temperature.
When he use temperature (hot water) to dissolve the sugar he is increasing the solubility of the sugar in the water, so in batch A we will have more quantity of sugar dissolved than in the batch B. The cooling of the solution at room temperature favors the formation of bigger sugar crystals in the process of crystallization.
From all of the above, the correct predicted observation is the option A: It is likely that more rock candy will be formed in batch A, for the increase of the solubility by the use of hot water. Also, you say that Rock candy is formed when excess sugar is dissolved in hot water followed by crystallization.
I hope it helps you!
How many moles of H2 are needed to produce 24 moles of NH3?
Answer:
36 mol of H2
Explanation:
The balanced equation of the reaction is given as;
3H2 + N2 --> 2NH3
From the reaction;
It takes 3 mol of H2 reacting with 1 mol of N2 to form 2 mol of NH3
3 mol of H2 = 2 mol of NH3
x mol of H2 = 24 mol of NH3
x = (24 * 3) / 2 = 36 mol of H2
What is the purpose of cell respiration?
to breath in food
to expel unwanted oxygen
to produce energy from food
Answer:
To produce energy from food
Explanation:
It's pretty much an energy cycle
A researcher observes a reaction and gathers the data in the table below. Observations Mass decreased after reaction Energy is released during reaction New substance is formed Which piece of evidence best identifies they type of reaction as nuclear or chemical? 1. Chemical, because energy is released during the reaction. 2.Nuclear, because energy is released during the reaction. 3.Nuclear, because the mass decreased after the reaction. 4.Chemical, because a new substance is formed.
The piece of evidence that best identifies the type of reaction as nuclear or chemical is: Chemical, because a new substance is formed. Option 4
In this scenario, the observation that a new substance is formed is a key characteristic of a chemical reaction. Chemical reactions involve the rearrangement of atoms to form different substances with distinct properties. The formation of a new substance indicates a chemical change has occurred.
The other pieces of evidence listed do not necessarily point to a nuclear reaction:
Chemical, because energy is released during the reaction: Energy can be released in both nuclear and chemical reactions, so this observation alone is not sufficient to determine the type of reaction.
Nuclear, because energy is released during the reaction: While energy can be released in nuclear reactions, it is not exclusive to them. Chemical reactions can also release energy, such as in exothermic reactions.
Nuclear, because the mass decreased after the reaction: This observation suggests a change in mass, which could be indicative of a nuclear reaction. However, it is important to consider that chemical reactions can also involve changes in mass, such as the formation of gases or dissolution of a solid.
Overall, the most conclusive evidence to identify the type of reaction is the formation of a new substance, which aligns with a chemical reaction.
Option 4
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a fisherman in a boat is drinking a of hot coffee. the large lake below his boat is full of cold water. which statement is an accurate comparison of the lake water and the coffee?
Answer:
see below
Explanation:
The lake will have more total thermal energy but the particles in the coffee will be moving faster.
A comparison of hot coffee and cold lake is, the heat from the coffee will be absorbed by the cold lake through convection method of heat transfer.
Conservation of energy
The principle of conservation of energy states that the total energy of an isolated system is always conserved.
Heat lost by the hot coffee = Heat absorbed by the cold lake
Heat transfer processHeat from the coffee will be absorbed by the cold lake through convection method of heat transfer.
Thus, a comparison of hot coffee and cold lake is, the heat from the coffee will be absorbed by the cold lake through convection method of heat transfer.
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Indicate the type of observation that is best represented by the figures below.
Identifying Types of Observations
qualitative
quantitative
Identifying Types of Observations
qualitative
quantitative
Identifying Types of Observations
qualitative
quantitative
The observation shown in the image is qualitative.
Chemical analysis will be; Qualitative
Quantitative :In a qualitative chemical analysis, we can determine the components of a substance. In a quantitative analysis, we want to determine the amount of every of the components of a substance. Both sorts of analysis are of very much important in chemistry.
From the image, we could observe a change in color . Qualitative analysis might be carried out by the use of chemical reagents which could give positive tests like as change in color to show the presence or absence of some constituents of a given substance.
Qualitative :Qualitative analysis provides the details of the presence or nonappearance of different chemical components in a unknown sample. Qualitative chemical analysis, deals with the branch of chemistry identification of elements or grouping of elements provided in a sample. This techniques employed in qualitative analysis vary in complexity, depending on the nature of the sample
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the outer most shell of an atom is called the valane shell. the number of electrons in this shell determines ________.
A gas has a volume of 50.0 mL at a temperature of 10.0 K and a pressure of 760. kPa. What will be the new volume when the temperature is changed to 20.0 K and the pressure is changed to 380. kPa?
To solve this problem using the gas laws, we need to use the Ideal Gas Law. This law states that the product of the pressure and the volume of a gas is proportional to the absolute temperature.
The equation of the Ideal Gas Law is the following:
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{\dfrac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2} } \end{gathered}$} }\)
Where:
P₁ = initial pressure = 760 kPaV₁ = initial volume = 50.0 mL = 0.050 LT₁ = initial temperature = 10.0 KP₂ = Final pressure = 380 kPaT₂ = final temperature = 20.0 KV₂ = Final volume = ?We clear for V₂:
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2=\frac{P_1V_1T_2}{P_2T_1 } } \end{gathered}$} }\)
Where:
P₁ = initial pressure V₁ = initial volumeT₁ = initial temperatureP₂ = Final pressureT₂ = final temperatureV₂ = Final volumeSubstituting the known values:
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2=\frac{760\not{kPa}\times0.050 \ L\times20.0\not{k} }{ 380\not{kPa}\times10.0\not{k} } } \end{gathered}$} }\)
\(\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2=\frac{760 \ L}{3800 } } \end{gathered}$} }\)
\(\boxed{\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{V_2\approx0.2 \ Liters} \end{gathered}$} }}\)
When the temperature changes to 20.0 K and the pressure changes to 380 kPa, the new volume will be approximately 0.2 L (200.0 mL).Living things are classified as producers or consumers according to
A) Their speed of movement
B) How they obtain food
C) The size of their communities
D) How they reproduce
Answer:
B
Explanation:
Your welcome! Have a great day!
Answer:
b
Explanation:
yw
How many H atoms are there in 0.510 moles of H
Answer:
No. of H atoms in 0.51 moles of H+ = 3.0713 * 10^23 atom
Explanation:
according to the definition of mole which states that the mole is the unit of amount of substance that equals Avogadro's number"Na = 6.022 * 10^23" (i.e. one mole of O2 contains 1Na of molecules, one mole of Ca = 1Na of atoms )
So
the number of atoms in 0.51 moles of H = 0.51 * 6.022 * 10^23 = 3.0713 * 10^23 atom
Part B
Next, you’ll test your hypothesis from part A by examining the reaction times of vinegar and baking soda in water at four different temperatures. You’ll carry out the reaction using water at room temperature (about 25°C), 40°C, 60°C, and 80°C. Make sure that you use the same amounts of vinegar and baking soda for all three three trials.
Gather all the materials, and perform these steps for each trial:
Heat at least
cup (60 milliliters) of water to the required temperature (refer to the data table). Water may be heated on a stove, on a hot plate, or in a microwave oven.
Measure and record the actual temperature of the water.
Measure 1 tablespoon (15 milliliters) of the water into the cup.
Add
teaspoon (1.5 grams) baking soda to the water, and stir until it is dissolved. The solution will be clear.
Measure 1 tablespoon (15 milliliters) of vinegar, but do not pour it into the cup yet.
Very quickly, do all of the following:
a. Pour the measured vinegar into the cup.
b. Start the stopwatch.
c. Stir or carefully swirl the substances in the cup.
The chemical reaction will produce bubbles. You’ll be able to see the bubbles and hear them pop. Watch and listen for when the reaction stops. When it looks and sounds like it has finished, stop the stopwatch.
Record the reaction time in the data table.
Discard the solution down the drain, and rinse the cup.
Repeat steps 1–9 of this procedure, doing three trials for each water temperature. Record the average temperature and reaction time for each set of the three trials. Read this math review to know how to calculate average of a data set.
The reaction time decreases as the temperature increases of the reaction mixture increases.
A sample record of results is:
Temperature (°C) Trial 1 Trial 2 Trial 3 Average25°C 11 seconds 11 seconds 11 seconds 11 seconds40°C 8 seconds 8 seconds 8 seconds 8 seconds60°C 5 seconds 5 seconds 5 seconds 5 seconds80°C 3 seconds 3 seconds 3 seconds 3 secondsWhat is the effect of an increase in temperature on reaction time?An increase in temperature leads to an increase in reaction rate or a decrease in reaction time.
The increase in temperature provides more thermal energy to the reactant molecules, which leads to an increase in the average kinetic energy of the molecules. As a result, more reactant molecules have sufficient energy to overcome the activation energy barrier and undergo successful collisions, leading to an increased reaction rate.
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if u coated the surface of a penny with a thin layer of a nonpolar liquid (oil) and then dropped alcohol and water onto the penny what would occur
When water is carefully dropped onto the surface of a penny, it can form a dome before spilling over the small lip around the penny's perimeter. Rubbing alcohol can also accumulate, but it will spill before forming a well-rounded dome.
What caused the water to spill over the penny?Cohesive forces are powerful, but not invincible. The force of gravity on the water molecules will eventually overcome the cohesive forces as a water drop builds up and out, usually bulging over the sides of the penny. The "skin" will rupture, allowing all the water to escape.
When the drops of water you add to the penny reach the penny's edge, the cohesion and surface tension of water become apparent.
Thus, When the water reaches the edge, a bubble or dome of water begins to form on top of the penny.
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H= aC+ b what does this mean?
Answer:
I think it's Hydrogen is equal to aCalcuim plus b
What is the molecular shape and bond angle at the indicated carbon?
Answer:
Tritons planar 120 degrees
Explanation:
The passage's author most vividly conveys the sense that Plumpp's poetry is like music when he
O uses words like "swing," "dance," and "sway" to characterize phrases in Plumpp's poems
O defines Plumpp as "the poet laureate of Chicago jazz and blues"
explains how long Plumpp has been writing about "Chicago jazz giants"
urges people to read Plumpp's poems and listen to the music Plumpp "immortalizes in print"
It is an amine, and it has less polar nitrogen-hydrogen and oxygen-hydrogen bonds.
A compound's boiling point is a physical characteristic. These intramolecular linkages between the molecules that make up a chemical affect these physical characteristics.
Alcohols and amino acids have the same kind of intermolecular linkages. The hydrogen bond is the name of this kind of bond.
The electrical attraction between a hydrogen atom from one molecule and an electronegative atom from a nearby molecule is known as a hydrogen bond.
The strength of the bond is in the following order: H.....F > H.....O > H......N
The H....N hydrogen bonds exist in amines, whereas the H....O hydrogen bonds exist in alcohols.
Consequently, the alcohol's hydrogen bonds are stronger and it will impart a higher boiling point on the compound.
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Answer:uses world like
Explanation:
Calculate q when 62.5 g of water is heated from 25.5°C to 80.7°C (specific heat capacity for water = 4.184J/g.K).
2.11 * 104)
6.67 * 103)
1.44 x 104)
2.78 x 104,
Answer:
Q = 1.44×10⁴ J
Explanation:
Given data:
Mass of water = 62.5 g
Initial temperature = 25.5°C
Final temperature = 80.7°C
Specific heat capacity of water = 4.184 J/g.K
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 80.7°C - 25.5°C
ΔT = 55.2 °C
Q = 62.5 g × 4.184 J/g.°C × 55.2 °C
Q = 14434.8 J
Q = 1.44×10⁴ J
how does the water cycle cause weather??
Answer:
The water cycle describes how water evaporates from the surface of the earth, rises into the atmosphere, cools and condenses into rain or snow in clouds, and falls again to the surface as precipitation. ... The cycling of water in and out of the atmosphere is a significant aspect of the weather patterns on Earth.
(This isn't my answer - but you can use it as reference :D )
Which substance has ionic bonds BaO?
BaO has ionic bonds because of electronegative difference.
Ionic bonds, also known as electrovalent bonds, are a type of linkage created in a chemical compound by the electrostatic attraction of ions with opposing charges. When the valence (outermost) electrons of one atom are permanently transferred to another atom, a bond of this kind is created. If an atom gains electrons, it becomes a negatively charged ion (cation), while if it loses them, it becomes a positively charged ion (cation) (anion). Following is a brief discussion of ionic bonds. To learn more, go to chemical bonding: the ionic bonding process.
Ionic or electrovalent compounds are produced by ionic bonding, and the compounds formed between nonmetals and alkali and alkaline-earth metals serve as the best examples of this type of compound. Actually, a polar covalent bond is the extreme form of an ionic bond.
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coonsider each of the following molecule in return describe the hybridization state of the central carbon
Al atom hybridization switches from being sp2 in AlCl3 to being sp3 in AlCl4.
What is hybridization?
Al has three bond pairs of electrons and no lone pairs of electrons in AlCl3. pondering the degree to which carbon atoms have hybridised. Hybridization state theory was first proposed by Linus Pauling in 1931 to explain the structure of molecules like methane (CH4). The steric number is calculated by adding the number of atoms an atom is bound to and the number of lone pairs it has. The atom is sp3 hybridised if the steric number is 4.
The atom is sp2 hybridised if the steric number is 3. Since C2 has three sigma bonds, its hybridization is sp2. Since C3 has two sigma bonds, C2 hybridises with C3.
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10. A 10.9ml sample of gas is collected over water at 21.0 C and 1.89 atm , what volume would you have at 25.0 C and 2.25 atm
Considering the combined law equation, you would have a volume of 9.28 mL at 25.0 C and 2.25 atm.
Boyle's lawBoyle's law establishes the relationship between the pressure and the volume of a gas when the temperature is constant.
This law says that volume is inversely proportional to pressure: if pressure increases, volume decreases, while if pressure decreases, volume increases.
Mathematically, Boyle's law states that the multiplication of pressure by volume is constant:
P×V= k
Charles's lawCharles's law establishes the relationship between the temperature and the volume of a gas when the pressure is constant.
This law says that the volume is directly proportional to the temperature of the gas: if the temperature increases, the volume of the gas increases, while if the temperature of the gas decreases, the volume decreases.
Mathematically, Charles' law states that the ratio of volume to temperature is constant:
\(\frac{V}{T}=k\)
Gay-Lussac's lawGay-Lussac's law establishes the relationship between the temperature and pressure of a gas when the volume is constant.
This law says that the pressure of the gas is directly proportional to its temperature: if the temperature increases, the pressure increases, while if the temperature of the gas decreases, the pressure decreases.
Mathematically, Gay-Lussac's law states that the ratio of pressure to temperature is constant:
\(\frac{P}{T}=k\)
Combined law equationCombined law equation is the combination of three gas laws called Boyle's, Charlie's and Gay-Lusac's law:
\(\frac{PV}{T}=k\)
Considering an initial state 1 and a final state 2, the following holds:
\(\frac{P1V1}{T1}=\frac{P2V2}{T2}\)
Volume in this caseIn this case, you know:
P1= 1.89 atmV1= 10.9 mLT1= 21 C= 294 K (being 0 C= 273 K)P2= 2.25 atmV2= ?T2= 25 C= 298 KReplacing in the combined law equation:
\(\frac{1.89 atmx10.9 mL}{294 K}=\frac{2.25 atmxV2}{298 K}\)
Solving:
\(\frac{1.89 atmx10.9 mL}{294 K}\frac{298K}{2.25 atm} =V2\)
9.28 mL= V2
Finally, you would have a volume of 9.28 mL at 25.0 C and 2.25 atm.
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b. How many kJ of heat are needed to completely vaporize 50.0g of water at 100°C? [Ans:113. kJ]
The amount, in kJ, of heat needed to completely vaporize 50.0g of water at 100°C is 118.8 kJ.
Heat of vaporization of waterThe heat needed to completely vaporize 50.0g of water at 100°C can be calculated using the following formula:
q = m x Hv
where:
q is the heat needed in joules (J)m is the mass of water in grams (g)Hv is the heat of vaporization of water which is approximately 40.65 kJ/mol at standard temperature and pressure.First, we need to convert 50.0g to moles by dividing by the molar mass of water which is approximately 18.015 g/mol3:
moles of water = 50.0 g / 18.015 g/mol moles of water = 2.776 mol
Thus:
q = (2.776 mol) x (40.65 kJ/mol) q = 112.8 kJ
In other words, 112.8 kJ of heat is needed to completely vaporize 50.0g of water at 100°C.
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A pentavalent cation atom has 20 and 15 neutrons as protons. Find the electron quantity and mass number respectively. (40 pts.) a) 20 and 15 b) 15 and 20 c) 15 and 35 d) 35 and 15 e) 10 and 20
Answer:
C.
Explanation:
Since the mass number is the number of protons and neutrons added together, the answer is 35. Since the questions are respectively electron quantity and mass number, the only answer choice with 35 as the second choice is C, so that is the correct answer.
can someone explain this better and simpiler?
Response:
Sorry but I think you forgot to attach or include something, thanks for the points tho!
Other:
Brainliest? Thanks!
The compound ammonia is composed of a single nitrogen atom bonded by single bonds to three hydrogens. How many electrons total are contained in the three single bonds?A. 6B. 5C. 3D. 4
Explanation:
First, let's draw the lewis structure for ammonia:
In a single bond, a pair of electrons is shared by the two atoms.
There are 3 single bonds with 2 electrons each, so there are 6 electrons.
Answer: A. 6
Using any data you can find in the ALEKS Data resource, calculate the equilibrium constant K at 25.0 °C for the following reaction. N2(g) + 3H2(g) --> 2NH3(g) Round your answer to 2 significant digits.
The Gibbs energy of reaction
ΔG is related to the equilibrium constant K
according to the expression
ΔG=ΔG∘+RTlnK
where ΔG∘ is the standard Gibbs energy, R is the universal gas constant with value 8.314×10−3kJmol, and T is the temperature.
At equilibrium, the Gibbs energy of reaction is equal to 0,
ΔG0=ΔG∘+RTlnK.
The standard Gibbs energy is the difference of the standard energies of formation of the products and reactants:
ΔG∘=∑nΔG∘f(products)−∑mmΔG∘f(reactants).
The variables n and m are the coefficients for each species.
From the resource, the standard energies of formation for each of these species are:
ΔG∘f(NOCl(g))=66.3kJmol
ΔG∘f(NO(g))=87.6kJmol
ΔG∘f(Cl2(g))=0kJmol
Giving this reaction a standard Gibbs energy of:
ΔG∘=[2ΔG∘f(NO(g))+ΔG∘f(Cl2(g))]−[2ΔG∘f(NOCl(g))]=[2⋅87.6kJmol+0kJmol−[2⋅66.3kJmol]=42.6kJmol
Using this data and the equation above, the equilibrium constant can be solved as:
K=exp[−ΔG∘RT]=exp⎡⎢⎢⎣−42.6kJmol(8.314×10−3kJmol)(298 K
)= 3.41×10−8
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if the body is moving with uniform acceleration then, eng of motion are given as s = u+v/2+t
Yes, s = u+v/2+t, where s is the displacement, u is the beginning velocity, v is the end velocity, and t is the time required, is the equation of motion for a body travelling with uniform acceleration.
The basic law of motion, which states that a body's rate of change in displacement is directly proportional to its velocity, provides the basis for this equation. The equation of motion for a body travelling with constant acceleration, s = ut + 1/2at2, may be used to derive it.
The equation of motion for a body travelling with uniform acceleration is given by replacing the value of an as (v-u)/t and getting s = u+v/2+t. This formula is only accurate when the body's acceleration is constant and uniform.
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Use the periodic table or graphic in lesson. Choose the correct electron configuration of carbon. 1s 22s 22p 4 1s 22s 22p 2 1s 22s 22p 1 1s 22s 12p 2
The Correct electron configuration of carbon as 1s² 2s² 2p². Option B.
To understand why this is the correct electron configuration, let's break it down step by step:
The atomic number of carbon is 6, which means it has six electrons. Electrons are distributed in energy levels or shells around the nucleus.
The first shell, known as the 1s orbital, can hold a maximum of 2 electrons. Therefore, the first part of the electron configuration is 1s², indicating that two electrons occupy the 1s orbital.
The second shell has two subshells: the 2s orbital and the 2p orbital. The 2s orbital can hold a maximum of 2 electrons, while the 2p orbital can hold a maximum of 6 electrons. In the case of carbon, after the 1s orbital, two more electrons occupy the 2s orbital. So far, we have 1s² 2s².
The remaining two electrons in carbon are placed in the 2p orbital. The 2p orbital consists of three separate p orbitals: 2px, 2py, and 2pz. Each p orbital can hold a maximum of 2 electrons. Therefore, the last part of the electron configuration for carbon is 2p², indicating that two electrons occupy the 2px and 2py orbitals. Option B is correct.
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Estimate 16.540 +9.32 by first rounding each number to the nearest tenth.plis i need it
Answer:
Explanation:
16.540 + 9.32 by rounding each number to the nearest tenth
so 16.540 the number in the tenth place is 5, if its 5 then you have to round up because 1-4 you need to round down, and 5-9 you would have to round up. if you round 16.540 to the nearest tenth would be 17.
Next, if 9.32 the number in the tenth place is 3, since is 5 below you would have to round down which rounds down to 9
So its 17+9 which your answer would be 26.
The temperature at which a liquid becomes a gas is the
point.
O A) freezing
O B) boiling
O C) condensation
O D) melting
Answer:
Boiling
Explanation:
Who were some of the scientists involved in discovering the atom?
Some of the scientists involved in discovering the atoms were John Dalton, J.J Thomas, Ernest Rutherford, Niels Bohr and Erwin Schödinger.
John Dalton recognized that atoms from a particular element differ from atoms and he came up with the Solid Sphere Model.
J.J Thomas recognized electrons as compounds of atoms and he came up with the plum pudding model.
Ernest Rutherford recognized that positive charge was located in the middle of the atom in the nucleus and he came up with the nuclear model.
Niels Bohr proposed stable electron orbit and explained the emission spectra of the elements. Besides, he came up with the planetary model.
Erwin Schödinger showed that electrons do not move in orbits around the nucleus but in clouds where their position is uncertain and he came up with the quantum model.
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Combination and decomposition reactions can be identified based on their typical characteristics. Which statements best describe the
characteristics of combination and decomposition reactions? Select all that apply.
D Combination reactions are typically exothermic and reactants are molecular compounds of single elements.
O Combination reactions are typically endothermic and the reactant is a compound with two or more elements.
Decomposition reactions are typically endothermic and the reactant is a compound with two or more elements.
Decomposition reactions are typically exothermic and reactants are molecular compounds of single elements.
The characteristics of combination and decomposition reactions are as follows:
Combination reactions are typically exothermic and reactants are molecular compounds of single elements (option A)Decomposition reactions are typically endothermic and the reactant is a compound with two or more elements (option C)What are combination and decomposition reaction?Combination reactions are chemical reaction where two or more elements or compounds combine to form a single compound.
Decomposition reaction is a reaction in which chemical species such as chemical compounds break up into simpler parts or elements. Usually, decomposition reactions require energy input i.e. endothermic.
Combination reactions give off energy as heat when compounds are formed by joining bonds i.e. they are exothermic.
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