Technician A says that the freezing point of a substance is the temperature at which the substance changes state from a solid to a liquid. Technician B says that the freezing point of a substance is the temperature at which the substance changes state from a liquid to a solid. Who is correct
Answer: Technician B
Explanation:
Technician B is correct. The freezing point of a substance is the temperature at which the substance changes state from a liquid to a solid.
Technician A is incorrect. On the other hand, the melting point of a substance is the temperature at which the substance changes state from a solid to a liquid.
What is the purpose of a catalyst in the production of hydrogen?
Select the correct answer.
- to increase the rate at which water molecules decompose
- to decrease the amount of oxygen produced
- to decrease the temperature of the reaction
- to increase the activation energy of the reaction
The purpose of a catalyst in the production of hydrogen is to increase the rate at which water molecules decompose.
What is a catalyst-A catalyst is a substance that increases the rate of a chemical reaction without itself being consumed or produced during the reaction. As a result, catalysts assist in speeding up chemical reactions while also decreasing the amount of energy needed for the reaction to occur. In hydrogen production, catalysts are used to speed up the decomposition of water into hydrogen and oxygen. The use of catalysts lowers the activation energy required for the reaction to occur, resulting in a faster reaction rate and lower operating temperatures.What is the process of hydrogen production?Hydrogen production has various methods, and one of the most commonly used methods is water electrolysis. In this method, water molecules are split into hydrogen and oxygen using an electric current passed through an electrode. Water is broken down into hydrogen and oxygen during the process, with the assistance of a catalyst. During this process, a catalyst like platinum or nickel is employed to speed up the chemical reaction of water decomposition.
When an electric current is applied to the catalyst, water molecules are broken apart, releasing hydrogen and oxygen atoms.Catalysts lower the activation energy of the reaction, allowing it to occur faster than it would otherwise. In hydrogen production, catalysts are crucial since they enable the reaction to occur at a lower temperature, reducing energy consumption and minimizing operating costs. As a result, the use of catalysts is essential to the production of hydrogen.
for such more questions on catalyst
https://brainly.com/question/21598276
#SPJ8
How long can crater fires burn?
Answer:
I would have to say More than 40 years
Identify the group number and generic outer electron configuration for a neutral main‑group element with the following two Lewis dot symbols.
X with 1 dot on the top, bottom and right
X with 1 dot on all sides
Answer: Answer to #1 is 3A and ns2np1
Answer to #2 is 4A and ns2np2
Explanation:Group number is the number of valance electrons and generic outer electron configuration has to add up to equal the number of valance electrons
The element in the first diagram is in group 13 while the element in the second diagram is in group 14.
The Lewis structure of an atom of an element is a representation of the number of valence electrons on the outermost shell of the atom of that element. Every group of elements have a generic electron configuration which represents the number of valence electrons contained by atoms of elements in that group.
In the first diagram, the element X belongs to group 3A(13) and has a generic outer electron configuration, ns2np1. In the second diagram, the element X is in group 4A(14) and has outer electron configuration ns2np2.
Learn more: https://brainly.com/question/4147359
What are the differences between molecule of an elements and molecules of a compound?
a compound is a pure substance made up of two or more elements chemically combined a molecule is defined as the smallest particle of an element which can exist separately elements are pure substances which can not be split into simple substances by chemical means the atom is defined as the smallest particle of an element which can take part in a chemical change so I think the difference between the molecule of a compound is bigger than the molecule of a compound
g) silver nitrate + magnesium chloride → silver chloride + magnesium nitrate
Answer:
AgNo3+Mgcl2--->Agcl2+Mg(No3)2
I hope this helps
Specific heat capacity is _____.
greater for metal than for wood
the amount of heat required to raise the temperature of 1g of a substance 1 oC
represented by the symbol, Q
all of these
Answer:
all of this
Explanation:
How much water will the measuring cup have if you poured 1/2 of it out?
Determine the mass in grams of 3.60 mol of H2 SO4
Answer:
Explanation:
There are 353 grams of H2SO4 in 3.60 moles of H2SO4.
Question 5
1.00 g of He, 14.0g F2, and 19.0 g Ar are placed in a 13.0-L container at 20.0 °C.
The total pressure (in atm) in the container is _____ atm.
1 point
Answer:
2.03 atm
Explanation:
Number of moles of He = 1g/4g/mol = 0.25 moles
Number of moles of F2 = 14.0g/38 g/mol = 0.37 moles
Number of moles of Ar=19.0g/40g/mol = 0.48 moles
Total number of moles = 0.25 + 0.37 + 0.48 = 1.1 moles
From;
PV=nRT
P= pressure of the gas mixture
V= volume of the gas mixture
n= total number of moles of the gas mixture
R= gas constant
T= temperature of the gas mixture
P= nRT/V
P= 1.1 × 0.082 × 293/13
P= 2.03 atm
The world is made up of
Answer:
Explanation:
The world is made up of living beings .
Describe what happens to the particles when a substance:
1. Melts
2. Freezes
3. Boils
4. Condenses
Which is the electron configuration for lithium?
1s2
2s3
1s22s1
1s12s2
Answer:
1s2, 2s1
Explanation:
Lithium is the first element in the 2nd row of elements meaning its 1s orbital is completely filled and 1 electron is in the 2s orbital.
Answer:
the answer is C
Explanation:
In the figure a cyclist moves A to B and then to C.he could also go through the shortest path AC. Depending on this fact solve the following questions: Find the length of AC .Find the displacement and total distance covered.
Answer:
hope it helps you see the attachment for further information
write any two conditions at which a body of certain mass weightless
Answer:
A body becomes weightless in a zero-gravity scenario and when a force is applied to a body that is equal and opposite to the force of gravity. If the body is falling only under the influence of gravity.
Answer:
A body becomes weightless in a zero-gravity scenario and when a force is applied to a body that is equal and opposite to the force of gravity.If the body is falling only under the influence of gravity.
Một hỗn hợp X gồm CH3OH; C2H5OH; phenol có khối lượng 28,9 gam phản ứng vừa hết với 100ml dung dịch NaOH 2M. Phần trăm theo khối lượng phenol là ? Biết C = 12; O = 16; H = 1; Na = 23. *
Answer: bạn viết phương trình Phenol + NaOH
=> nNaOH = nPhenol = 0,2 mol
m Phenol = 0,2x94 = 18,8 gam
%mPhenol = 18,8/28,9% = 65,05
Explanation:
An atom with 6 protons and 8 neutrons is an)
Answer: carbon (C)
Explanation:
Convert the following absolute temperatures to centigrade.
i) 0 K
ii) 298 K
iii) 323 K
iv) 423 K
SHOW STEP BY STEP
Answer:
0 K
[tex]{ - \bf{273 \degree C}}[/tex]
298 K
[tex]{ \tt{ = 298 - 273}} \\ = { \bf{25 \degree C }}[/tex]
323 K
[tex]{ \tt{ = 323 - 273}} \\ = { \bf{50 \degree C}}[/tex]
423 K
[tex]{ \tt{ = 423 - 273}} \\ = { \bf{150 \degree C}}[/tex]
1.T=[£+273]
=273
It is because kelvin temperature is absolute zero.
what is the percentage composition of water in crystallization of oxalic acid
Answer:
5.17 percentage is water
Explanation:
answer from gauth math
c. The element in group 2 and period 3 is -
Answer:
Magnesium
Explanation:
Hope this helps!
What is the mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water?
The mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water is 29.7%.
What is mass percent ?Mass percent is a means to describe a component in a specific combination or to convey a concentration. The mass percentage used to describe the solution composition indicates the mass of solute contained in a given mass of solution.
To determine the mass percent of an element in a compound, we divide the mass of the element in one mole of the compound by the compound's molar mass and multiply the result by 100.
Given:
Number of moles = 0.64 moles
Moles of sodium fluoride = Given mass/molar mass
0.64 moles = Mass / 42
Mass = 26.88gram
Mass % = Mass of solute/ mass of solution × 100
= 26.88/90.48 × 100
= 29.7 %
Thus, 29.7 % is the mass percent of a sodium fluoride solution prepared by dissolving 0.64 moles of sodium fluoride into 63.5 grams of water
To learn more about the mass percent, follow the link;
https://brainly.com/question/5394922
#SPJ6
can you answer with working out
How is a slump different from creep?
Answer:
Is this chemistry or ELA!
Explain Froath Flotation Method!
Explanation:
a process for separating minerals from gangue by taking advantage of the differences in their hydrophobicity.
I believe that is accurate
hope this helped have a nice day
and mark me brainiest :)
What is the oxidation state of fluorine (F)?
The Periodic Table
A.-2
B. +1
C. -1
D. +2
Answer:
It is C. -1
Explanation:
[tex] { \underline{ \sf{ \blue{christ \: † \: alone}}}}[/tex]
Can compound take part in chemical reaction?
Answer:
YES!
Explanation:
- calculate relative formula mass
[N=14, O=16, Mg=24, Al=27]
1) Mg(NO3)2
- calculate relative molecular mass
[H=1, C=12, O=16]
1) C4H10
2) CH3COOH
Mg(NO3)2:-
[tex] \\ \sf \longmapsto \: 24u+2(14u+3\times 16u)[/tex]
[tex] \\ \sf \longmapsto \: 24u+2(14u+48u)[/tex]
[tex]\\ \sf \longmapsto \: 24u+2(62u)[/tex]
[tex] \\ \sf \longmapsto \: 24u+(124u)[/tex]
[tex] \\ \sf \longmapsto \: 148u[/tex]
What is the pressure in atm exerted by 1.8 g of H2 gas exert in a 4.3 L balloon at 27ºC? R = 0.821(L*atm) / (mol*K)
kakamc cjdismxsjxj xjcodmd xksowmd x
The pressure in atm exerted by 1.8 g of H₂ gas exert in a 4.3 L balloon at 27ºC is 5.12 atm
What is Ideal gas law ?The ideal gas law (PV = nRT) relates the macroscopic properties of ideal gases. An ideal gas is a gas in which the particles (a) do not attract or repel one another and (b) take up no space (have no volume).
Let's convert grams to moles (via molar mass).
Molar Mass (H₂) : 2 (1.008 g/mol)
Molar Mass (H₂) : 2.016 g/mol
1.8 grams H₂ 1 mole
---------------------- x ---------------------- = 0.893 moles H₂
2.016 grams
The Ideal Gas Law equation looks like this:
PV = nRT
In this equation,
P = pressure (atm) V = volume (L) n = moles R = Ideal Gas Constant (0.0821 L*atm/mol*K)T = temperature (K)After converting Celsius to Kelvin, you can put the given values into the equation and simplify to find the pressure.
P = ? atm R = 0.0821 L*atm/mol*K
V = 4.3 L T = 27 °C + 273.15 = 300.15 K
n = 0.893 moles
PV = nRT
P (4.3 L) = (0.893 moles) (0.0821 L*atm/mol*K)( 300.15 K)
P (4.3 L) = 22.0021
P = 5.12 atm
Therefore, The pressure in atm exerted by 1.8 g of H₂ gas exert in a 4.3 L balloon at 27ºC is 5.12 atm
Learn more about Ideal gas here ;
https://brainly.com/question/8711877
#SPJ2
please help I will mark your answer as brainliest!!!!
Give the structural formula of CH3CH(CH3)CH3
In the structure, we essentially have a Carbon with 3 methyl groups and a hydrogen attached to it
PLZ HELP Matthew wants to study how the body responds when the skin is broken. He learns that particles in the blood clump together at the site of the wound to stop the bleeding while the skin heals. Which of the following body systems is involved in carrying the blood to the site of the wound?
A. Cardiovascular
B. Skeletal
C. Respiratory
D. Muscular
Answer:
A, Cardiovascular system
cardiovascular system