Answer:
Volume is 1.065L
Explanation:
Hello,
We can easily solve this problem by using general gas equation.
PV / T = K
P1V1/T1 = P2V2/T2
Data;
P1 = 3.0atm
P2 = 1.0atm
T1 = 20°C = (20 + 273.15)K = 293.15K
T2 = 20°C = (20 + 273.15)K = 293.15K
V1 = 355mL = 0.355L
V2 = ?
From the data given, we can substitute it into the equation,
(P1 × V1) / T1 = (P2 × V2) / T2
(3.0 × 0.355) / 293.15 = (1.0 × V2) / 293.15
1.065 = 1.0V2
Divide both sides by 1.0
V2 = 1.065L
The volume of CO₂ released is 1.065L
Iron oxide reacts with carbon monoxide to produce iron and carbon dioxide, with the balanced chemical equation Fe2O3 + 3CO —> 2Fe + 3CO2. What does this tell you
about the relative amounts of iron oxide and iron consumed and produced in this equation?
A. For every two moles of iron oxide consumed, one mole of iron is produced,
B. For every two grams of iron oxide consumed, one gram of iron is produced.
C. For every gram of iron oxide consumed, two grams of iron are produced
D. For every mole of iron oxide consumed, two moles of iron are produced.
Answer:
Option D. For every mole of iron oxide consumed, two moles of iron are produced.
Explanation:
The balanced equation for the reaction is given below:
Fe2O3 + 3CO —> 2Fe + 3CO2
From the balanced equation above,
1 mole of iron oxide, Fe2O3 reacted with 3 moles of carbon monoxide, CO to produce 2 moles of iron, Fe and 3 moles of carbon dioxide, CO2.
Thus, with a careful observation of the equation, we can conclude that for every 1 mole of iron oxide, Fe2O3 consumed, 2 moles of iron, Fe are produced.
If Sulfonamides are toxic to Bacteria by stopping folic acid synthesis, and since folic acid is also very important for humans Does this make Sulfonamides toxic to humans? And why?
Answer:
No
Explanation:
Most Sulfonamides are antibiotics that kill bacteria but not human cells. They work by distrupting the production of dihydrofolic acid (form of folic acid that human/bacteria cells use for protein production).
how many dots would go around xenon in electron dot diagram
Answer:
8
Explanation:
Since Xe (xenon) is a noble gas, it has 8 valence electrons. It's outer shell is full and it is a stable element and doesn't like to react. Therefore, since the electron dot diagram is about valence electrons, 8 would be your answer.
hello:) is hydrogen chloride and hydrochloride acid the same??
Answer:
No because hydrogen chloride is gas and hydrochloric acid is (as stated in the name) an acid. The formula for hydrogen chloride is HCI(g), the little g states that the compound is a gas and the formula for hydrochloric acid is HCl(aq) and the little aq means aqueous.
Answer:
no. they are not the same
Explanation: Although, they both do have the same chemical formula HCL, they differ in their states of matter. Hydrogen chloride is a gas whereas hydrochloric acid is a solution of hydrogen chloride gas and water( creates an aquaeous solution). Hydrochloric acid is highly corrossive.
Freezing point depression is:
A. When a substance does not need to be as cold as normal in order to freeze.
B. When a substance freezes and then quickly drops in temperature.
C. When a substance drops in temperature until it freezes, then quickly rises in
temperature but stays frozen.
D. When a substance must be colder than normal in order to freeze.
Reset Selection
When a substance must be colder than normal in order to freeze, is freezing point depression. The correct option is D.
What is freezing point?Freezing, also widely recognized as solidification, is a phase transition that occurs when the temperature of a liquid falls below its freezing point.
Freezing point depression occurs when a material must be colder than normal to freeze.
Thus, the correct option is D.
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PLEASE HELP!
An athlete eats food in order to get energy for their competition that day. What type of energy conversion is happening in this example?
kinetic to electrical
electric to chemical
chemical to electrical
chemical to kinetic
Answer:
Chemical energy to kinetic energy.
Kinetic energy means movement, which is the energy needed for athlete
An athlete eats food in order to get energy for their competition that day. Chemical energy is changing to kinetic energy in this example. Therefore, the correct option is option D.
What is energy conservation?By using less energy services, energy conservation aims to cut down on unnecessary energy use. This can be accomplished through modifying one's behavior to consume less service or by utilizing energy more efficiently. Efficiency in energy consumption is a way to conserve energy.
In addition to cost, water, or energy savings, this has a number of benefits including a decrease in emissions of greenhouse gases as well as a lower carbon footprint. Green engineering techniques extend the life of machine parts that transform energy from one type to another. An athlete eats food in order to get energy for their competition that day. Chemical energy is changing to kinetic energy in this example.
Therefore, the correct option is option D.
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What is the oxidation state of each element in the compound CaS04? Include +or - in your answer as appropriate
Answer:therefore the oxidation state of sulphur is +6 in the compound CaSO4.
Explanation:
For the galvanic (voltaic) cell Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s) (E°= 0.77 V at 25°C), what is [Fe2+] if [Mn2+] = 0.040 M and E = 0.78 V?
Assume T is 298 K
Answer:
0.01836 M
Explanation:
Again the reaction equation is;
Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s)
E°cell= 0.77 V
Ecell= 0.78 V
[Mn2+] = 0.040 M
[Fe2+] = the unknown
n=2
From Nernst's equation;
Ecell= E°cell- 0.0592/n log Q
0.78= 0.77 - 0.0592/2 log [Fe2+] /[0.040]
0.78-0.77= - 0.0592/2 log [Fe2+] /[0.040]
0.01/ -0.0296= log [Fe2+] /[0.040]
-0.3378= log [Fe2+] /[0.040]
Antilog(-0.3378) = [Fe2+] /[0.040]
0.459= [Fe2+] /[0.040]
[Fe2+] = 0.459 × 0.040
[Fe2+] = 0.01836 M
The Fe ion concentration in the galvanic cell has been 0.0186 M.
The Nernst equation has been used for the determination of the voltage of the galvanic cell.
It can be given as:
[tex]\rm E_c_e_l_l\;=\;E_0\;-\;\dfrac{0.059}{n}\;\times\;log\;\dfrac{[Fe^+]}{[Mn^2^+]}[/tex]
where, n = number of electrons transfer = 2
[tex]\rm E_0[/tex] = initial voltage = 0.77 V
[tex]\rm E_c_e_l_l[/tex] = cell voltage = 0.78 V
Iron ion concentration = 0.040 M
Susbstituting the values:
0.78 = 0.77 - [tex]\rm \dfrac{0.059}{2}\;\times\;log\;\dfrac{[Fe^2^+]}{[0.040]}[/tex]
0.78 - 0.77 = -0.0296 [tex]\rm \times\;log\;\dfrac{[Fe^2^+]}{[0.040]}[/tex]
-0.03378 = [tex]\rm log\;\dfrac{[Fe^2^+]}{[0.040]}[/tex]
antilog (-0.03378) = [tex]\rm \dfrac{[Fe^2^+]}{0.040}[/tex]
Iron ion concentration = 0.0186 M
Thus, the Fe ion concentration in the galvanic cell has been 0.0186 M.
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a compound contains 28.6 magnesium 14.3 carbon 57.1 oxygen what is the empirical formula
Answer:
Option 3
[tex]MgCO_{3}[/tex]
Explanation:
These are the steps for empirical forumla
1) If given percentage, assume everything in grams
2) Convert those grams to moles (using specific molar mass of each unique element)
3) Divide all the moles by the smallest mole you discovered.
4) Answer will be close to a whole number for each element and that's the answer.
First step, 28.6 g Mg, 14.3 g C, 57.1 g O
Second step:
28.6/24.305 = 1.1767 Mg
14.3/12.01= 1.1907 C
57.1/16.00 = 3.5688 O
Third step:
1.1767/1.1767 = 1 Mg
1.1907//1.1767 ~ 1 C
3.5688/1.1767 ~ 3 O
Put everything together you get!
[tex]MgCO_{3}[/tex]
The empirical formula for the compound is:
C. [tex]MgCO_3[/tex].
What is an Empirical formula?A chemical formula showing the simplest ratio of elements in a compound rather than the total number of atoms in the molecule.
Given:
28.6 g Mg, 14.3 g C, 57.1 g O
In order to determine empirical formula we will divide mass of each given element with the molar mass of the respective element.
[tex]\frac{28.6}{24.305} = 1.1767 Mg[/tex]
[tex]\frac{14.3}{12.01}= 1.1907 C[/tex]
[tex]\frac{57.1}{16.00} = 3.5688 O[/tex]
Dividing each mass with the lowest mass:
[tex]\frac{1.1767}{1.1767 } = 1 Mg[/tex]
[tex]\frac{1.1907}{1.1767 } = 1 C[/tex]
[tex]\frac{3.5688}{1.1767} =3 O[/tex]
Thus, the empirical formula for the compound is [tex]MgCO_3[/tex].
Therefore, option C is correct.
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All of the following are units for pressure except _____. A. Pa B. psi C. atm D. Hg
Answer:
B. psi
Explanation:
Pa is Pascal
atm is atmosphere
Hg is Mercury
hope it helps.
A limestone plateau has no surface water. All the water is pulled underground through cracks and crevices in the surface. What most likely will cause the underground of the plateau to change over time? Physical weathering due to frost wedging Physical weathering due to abrasion Chemical weathering due to oxygen Chemical weathering due to water huryyyyyyyyyyyy
Answer:
Chemical weathering due to water
Explanation:
Since all the water is pulled underground through cracks and crevices on the surface, it makes the limestone plateau have no surface water. Meanig the most likely cause for having the underground of the plateau to change over time is the chemical weathering due to water.
In contrast to erosion, which involves movement, weathering occurs on the spot with little to no movement. Therefore, Chemical weathering due to water will cause the underground of the plateau to change over time.
What is weathering?Rocks, soils, and minerals are broken down by a variety of factors, including interaction with water, biological creatures, and the earth's atmosphere, during weathering, an essential natural process.
Chemical weathering, often referred to as biological weathering, is the breakdown of soils, and rocks as a result of exposure to chemicals in the atmosphere or chemicals produced biologically. Chemical weathering due to water will cause the underground of the plateau to change over time.
Therefore, Chemical weathering due to water will cause the underground of the plateau to change over time.
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Soil is a valuable resource because it
a. is important to all living things on land.
b. contains sand and gravel.
c. is rich in decomposers.
d. has all three soil horizons.
Answer:
It is important to all living things on land
1. Predict the major organic product(s) of the reactions below. If multiple major products are expected,
please include them all. Minor products need not be shown. If an organic salt is the product, please
include the counterion. Assume 1 equivalent unless stated, is a solvent, catalytic, or an
oxidizing reducing agent
which subject
Explanation:
write properly
The kinetic-molecular theory of gases says A. the particles of a gas move independently of each other. B. the particles in a gas move rapidly. C. the particles in a gas are far apart. D. all of the above.
Answer:
D. all of the above.
Explanation:
The kinetic-molecular theory of gases suggests that; the particles of a gas move independently of each other, the particles in a gas move rapidly, the particles in a gas are far apart.
Hope it helps.
What is the mass of a sample of copper that contains 4.78 x 1023 atoms?
Answer:
50.45679
Explanation:
mass of 1 mole(6.02 x 10^23atoms) of copper: 63.546g
so,
63.546g x 4.78 x 10^23 / 6.02 x 10^23 = 50.45679g (you could round this to the nearest decimal if u wish so)
Write the net ionic equation describing the reaction between aluminum metal and Fe3+ ions in solution that produces dissolved Al3+ and Fe2+ ions. Be sure to include all states of matter.
Answer:
Al(s) + Fe³⁺ ----> Al³⁺(aq) + Fe²⁺(aq)
Explanation:
The reaction between aluminium metal with an aqueous solution of Fe³⁺ ions to produce Al³⁺ ions and Fe²⁺ ions is a redox reaction in which the aluminium metal is oxidized while the Fe³⁺ ions are reduced.
Oxidation occurs if the oxidation number of an element or ionic species increases in the positive direction whereas reduction occurs when the oxidation number of the reacting species decreases.
The oxidation number of aluminium increases from 0 to +3 whereas the oxidation number of iron reduces from +3 to =2 in the given reaction.
In a net ionic equation, only the species participating in the reaction are shown.
The equation is given below;
Al(s) + Fe³⁺ ----> Al³⁺(aq) + Fe²⁺(aq)
_____ processes inside the Earth cause heat to be generated within it. What one word finishes the sentence?
Answer: Radioactive Decay
Explanation: Radioactive decay is a process that breaks atomic nuclei up, and releases energy. This energy can be in the form of heat and radiation. An example of this would be the formation of geothermal energy. This type of sustainable energy that produces heat from below the surface of the earth by this process of radioactive decay.
Hope this helps:)
Geological processes inside the Earth cause heat to be generated within it.
The word that finishes the sentence is "geothermal." Geothermal processes inside the Earth cause heat to be generated within it. Geothermal energy refers to the heat energy derived from the Earth's internal processes, such as radioactive decay of minerals, residual heat from the planet's formation, and heat transfer from the Earth's core.
These geothermal processes contribute to the overall heat budget of the Earth and play a crucial role in various geological phenomena, including plate tectonics, volcanic activity, and the formation of geothermal reservoirs. The heat generated from these processes can be harnessed for various applications, such as generating electricity through geothermal power plants, heating buildings through geothermal heating systems, and providing hot water for industrial and domestic use.
Geothermal energy is considered a renewable and sustainable energy source because it relies on the continuous heat production within the Earth. By tapping into this natural heat, we can utilize it as an alternative to fossil fuels and reduce greenhouse gas emissions. The study and understanding of geothermal processes are important for harnessing this valuable energy resource and for gaining insights into the Earth's dynamic internal structure and processes.
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What must occur in order for a chemical reaction to be specifically classified as endothermic instead of exothermic?
A)Atoms are rearranged.
B)Chemical bonds are formed.
C)Energy is released in the form of heat.
D)Energy is absorbed in the form of heat.
An exothermic reaction creates heat.
The answer would be c) energy is released in the form of heat.
A chemical reaction is classified as exothermic or endothermic based on the direction of heat flow during the reaction
The correct option for what must occur for a reaction to be classified as an exothermic reaction is option C
C) Energy is released in the form of heat
The reasons the above value is correct are;
An exothermic reaction is one in which energy in the form of light, heat or other forms because the sum of the energy in the product is less than the sum of energy contained in the reactants
Therefore, for a chemical reaction to be specifically classified as an endothermic reaction, instead of an exothermic reaction, is energy, in the form of heat (or light) must be released
The correct option is option C
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Fill in the term that best completes the statement. Work transfer _______ between two objects.
Answer:energy
Explanation:
Can u please help me , I’m stuck it’s question e
Answer:
salt
Explanation:
xdcfgvh jhg
In ammonia, NH3, the hydrogen atoms orient themselves as far away as
possible from each other because this arrangement _____.
Answer:
The hydrogen atoms in ammonia orient themselves as far away as possible from each other because this arrangement minimizes repulsion between electron groups present in the molecule
Explanation:
A covalent bond is formed between two atoms when a pair of electrons is shared between two atoms. This forms an electron group which occupies the the space between the atoms. Similarly, a lone pair of electrons defines an electron group that is located primarily on one atom.
An ammonia molecule is made up of three hydrogen atoms covalently bonded to a central nitrogen atom. The electron groups in an ammonia molecule consists of a lone pair of electrons found on the nitrogen atom alone and three bonding pairs of electrons shared between the nitrogen and hydrogen atoms.
According to the VSEPR (valence shell electron pair repulsion) theory, since electron groups are negatively charged regions, they repel one another. Therefore,the best arrangement of a given number of electron groups is the one that minimizes the repulsion among them.
In accordance with the VSEPR theory, the hydrogen atoms in ammonia orient themselves as far away as possible from each other because this arrangement minimizes repulsion between electron groups present in the molecule.
What is always true of a strong acid?
Answer:
The strong acid provides more H+ ion whereas the weak acids produce less H+ in the aqueous solution resulting in less amount of electricity conduction in the solution.
Weak acid- lesser amount of H+ produced
Strong acid- greater amount of H+ ( proton) produced
Which process describes the passing of nutrient molecules from the digestive system into the blood?
Answer:
The liver has multiple functions, but two of its main functions within the digestive system are to make and secrete an important substance called bile and to process the blood coming from the small intestine containing the nutrients just absorbed. The liver purifies this blood of many impurities before traveling to the rest of the body.
Explanation:
Answer:
"Absorption is the process by which nutrient molecules pass through the wall of your digestive system into your blood. Materials that are not absorbed, such as fiber, are eliminated from the body as wastes."
Explanation:
Which of the following compounds in the main group is a metalloid?
A. Arsenic
B. Potassium
C. Chlorine
D. Indium
Answer:
A. Arsenic
Explanation:
Arsenic is a metalloid. Arsenic has properties of both metals and non-metals that is why it is a metalloid.
Potassium, chlorine, and indium do not have both properties of metals and non-metals, therefore they are not metalloids.
Answer: A
Explanation: have a nice day
Cosmone has the molecular formula C15H26O. Calculate the number of moles of carbon in a 8.35-mol sample of cosmone. Calculate the mass of a sample of cosmone that contains 6.58 x 1019atoms of hydrogen. Calculate the number of atoms of carbon m 8.00-g of cosmone.
Answer:
1) 125.25 moles of carbon
2) 9.35 × 10⁻⁴ grams of cosmone
3) 1.44×10²¹ atoms of carbon
Explanation:
1) The given compound, cosmone, with molecular formula C₁₅H₂₆O has 15 toms f carbon per molecule, therefore, we have
8.35 mole of C₁₅H₂₆O, will contain 15 × 8.35 moles of carbon which is 125.25 moles of carbon
2) The number of moles of hydrogen in 6.58 × 10¹⁹ atoms of hydrogen = 6.58 × 10¹⁹/(6.02 × 10²³) = 1.09 × 10⁻⁴ moles
1 mole of cosmone contains 26 moles of hydrogen, therefore;
1 mole of hydrogen will be contained in 1/26 moles of cosmone
1.09 × 10⁻⁴ moles of hydrogen will be contained in 1/26 × 1.09 × 10⁻⁴moles of cosmone = 4.204 × 10⁻⁶ moles of cosmone
The molar mass of cosmone = 15*12.0107 + 26*1.00784 + 1 * 15.999 = 222.36334 g/mol
Therefore, the mass of 4.204 × 10⁻⁶ moles of cosmone = 4.204 × 10⁻⁶×222.36334 = 9.35 × 10⁻⁴ grams of cosmone
3) The number of moles in 8.00 g of cosmone = 8/222.36 = 0.036 moles
Therefore, number of moles of carbon atoms in 0.036 moles of cosmone = 0.036/15 moles which is 0.0024 moles of carbon;
1 mole of carbon atoms contains 6.02 × 10²³ atoms. therefore;
0.0024 moles of carbon will contain 6.02 × 10²³ × 0.0024 carbon atoms which is 1.44×10²¹ atoms of carbon.
1) The number of moles of carbon are 125.25
2) The mass of sample 9.35 × 10⁻⁴ grams
3) The number of atoms of carbon 1.44×10²¹
Calculation for number of moles:1) Molecular formula for cosmone is C₁₅H₂₆O, it has 15 atoms of carbon per molecule, therefore, we have
8.35 mole of C₁₅H₂₆O, will contain 15 * 8.35 moles of carbon which is 125.25 moles of carbon
2) The number of moles of hydrogen in 6.58 × 10¹⁹ atoms of hydrogen
= 6.58 × 10¹⁹/(6.02 × 10²³)
= 1.09 × 10⁻⁴ moles
1 mole of cosmone contains 26 moles of hydrogen, thus;
1 mole of hydrogen will be contained in 1/26 moles of cosmone
1.09 × 10⁻⁴ moles of hydrogen will be contained in 1/26 × 1.09 × 10⁻⁴moles of cosmone = 4.204 × 10⁻⁶ moles of cosmone
The molar mass of cosmone =222.36334 g/mol
Thus, the mass of 4.204 × 10⁻⁶ moles of cosmone
= 4.204 * 10⁻⁶ * 222.36334
Mass of sample = 9.35 × 10⁻⁴ grams of cosmone
3) The number of moles in 8.00 g of cosmone
= 8/222.36
= 0.036 moles
The number of moles of carbon atoms in 0.036 moles of cosmone = 0.036/15 moles which is 0.0024 moles of carbon;
1 mole of carbon atoms contains 6.02 * 10²³ atoms. Thus,
0.0024 moles of carbon will contain 6.02 * 10²³ * 0.0024 carbon atoms which is 1.44 * 10²¹ atoms of carbon.
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Use the reaction l2(s) = 12(9), AH = 62.4 kJ/mol, AS = 0.145 kJ/(mol-K), for
this question
At what temperature is the reaction at equilibrium?
A. 157 K
B. 62 K
C. 0.002 K
D. 430 K
Answer: D. 430 K
Explanation:
Using Gibbs Helmholtz equation:
[tex]\Delta G=\Delta H-T\Delta S[/tex]
[tex]\Delta G[/tex] = Gibbs free energy
[tex]\Delta H[/tex] = enthalpy change = 62.4 kJ/mol
[tex]\Delta S = entropy change = 0.145 kJ/mol K
T = temperature in Kelvin
[tex]\Delta G[/tex] = +ve, reaction is non spontaneous
[tex]\Delta G[/tex]= -ve, reaction is spontaneous
[tex]\Delta G[/tex]= 0, reaction is in equilibrium
At equilibrium : [tex]T\Delta S=\Delta H[/tex]
[tex]T=\frac{\Delta H}{\Delta S}[/tex]
[tex]T=\frac{62.4}{0.145}[/tex]
[tex]T=430K[/tex]
Thus at 430 K , the reaction is at equilibrium.
Use the reaction I2(s) ⇌ l2(g), ΔH = 62.4 kJ/mol, ΔS+ 0.145 kJ/(mol⋅K), for this question. At what temperature is the reaction at equilibrium?
430 K
The rate constant for the first-order decomposition of cyclobutane at 500 °C is 9.2 x 10−3 s−1. How long will it take (in seconds) for 80.0% of a sample of C4H8 to decompose?
The time taken to complete the reaction is 179 seconds.
Rate of reaction?Rate of reaction is the time taken for a reaction to attain completion. From the data presented, we have;
Initial concentration = No
Final concentration = No - (0.8No) = 0.2No
rate constant = 9.2 x 10−3 s−1
time taken = t
Given that;
N =Noe^-kt
0.2No =Noe^-( 9.2 x 10−3 t)
0.2 = e^-( 9.2 x 10−3 t)
ln(0.2) = 9.2 x 10−3 t
t = ln(0.2)/-9.2 x 10−3
t = -1.609/-0.009
t= 179 seconds
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seasonal variation in Earth's climate are caused by
a Earth's rotation
b Earth's tilt
c Earth's magnetic field
d Earth's precession
Answer: B: Earths tilt
Explanation:
Seasonal variation occurs because the Earth is tilted on its axis by 23.5˚. As Earth orbits the sun, its orientation to the sun changes.
The chemical formula for barium oxide is BaO. A chemist determined by measurements that 0.065 moles of barium oxide participate in a chemical reaction. Calculate the mass of barium oxide that participates.
Answer:
9.97 g (corrected to 3 significant figures.)
Explanation:
mass = no. of moles x molar mass
Atomic mass of Barium = 137.327; oxygen = 15.999,
so the molar mass of BaO = 137.327 + 15.999
=153.326
Hence, the mass is
0.065 x 153.326
=9.97 g (corrected to 3 significant figures.)
Answer:
9,97 g to the nearest hundredth.
Explanation:
Using the relative atomic masses of Barium and Oxygen:
1 mole of BaO has a mass of 137.327 + 16 = 153.327 g.
So 0.065 moles has a mass of 153.327 * 0.065
= 9.966 g.
The arrows in the chart below represent phase transitions.
Which arrows represent the phase transitions in which heat energy is gained?
1, 2, and 3
2, 3, and 5
3.4. and 5
4.5 and 6
Answer:
a. 1,2,and 3.
Explanation:
When something turns liquid, e.g. metal, you need to heat it. When something turns gas, e.g. water, you need to heat it. And when something goes directly from solid to gas, e.g. dry ice, carbon dioxide, you need to add heat to it. hope this helps! Please mark brainiest.