Answer:
4A
Explanation:
on the periodic table
A system performed 145 kJ of work on the surroundings and absorbed 105 kJ of heat from the surroundings. What is the change in energy of the system?
Answer:
250 kJ
Explanation:
Step 1: Given data
Work performed by the system (w): 145 kJ (By convention, when the system performs work on the surroundings, w > 0)Heat absorbed by the system (q): 105 kJ (By convention, when the system absorbs heat from the surroundings, q > 0)Step 2: Calculate the change in the internal energy of the system
The internal energy of a thermodynamic system is the energy contained within it. We can calculate the change in the internal energy (ΔE°) using the following expression.
ΔE° = q + w
ΔE° = 105 kJ + 145 kJ = 250 kJ
What is required to cause change in matter
Answer:
Adding or removing energy from matter causes a physical change as matter moves from one state to another. For example, adding thermal energy (heat) to liquid water causes it to become steam or vapor (a gas). And removing energy from liquid water causes it to become ice (a solid). ... Most liquids contract as they freeze.
Explanation:
have a nice day
Please I have a D in chem and grades close tomorrow ;-;
Which of the following polyatomic lons will form an lonic compound with a single sodium lon?
co₂2-
нсо3^1-
S04^2-
S03^2-
What is the degree of oxidation of a simple substance
Answer:
The oxidation state of a free element (uncombined element) is zero. For a simple (monoatomic) ion, the oxidation state is equal to the net charge on the ion. For example, Cl– has an oxidation state of -1. When present in most compounds, hydrogen has an oxidation state of +1 and oxygen an oxidation state of -2
which of the following is an isotope of hydrogen
8)
C(diamond) → C(graphite)
delta G° = -2.9 kJ/molrxn
Which of the following best explains why the reaction represented above is not observed to occur at
room temperature?
(A) The rate of the reaction is extremely slow because of the relatively small value of AGº for
the reaction.
(B) The entropy of the system decreases because the carbon atoms in graphite are less ordered
than those in diamond.
(C) The reaction has an extremely large activation energy due to strong three-dimensional
bonding among carbon atoms in diamond.
(D) The reaction does not occur because it is not thermodynamically favorable.
Answer: its b hope this helps.
Explanation:
When 240 mg of a certain molecular compound X are dissolved in 35.0 g of dibenzyl ether ((C6H5CH2)2O), the freezing point of the solution is measured to be 1.0 °C. Calculate the molar mass of X If you need any additional information on dibenzyl ether, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to the correct number of significant digits.
Answer: MM = 16.55 g/mol
Explanation: Freezing point depression is a phenomena that explains why adding a solute to a solvent decreases the solvent freezing point: when a substance begins to freeze, its molecules slows down and rearrange itself forming a solid. If a solute is added, the molecules from the solvent interfere in the formation of the solid. To guarantee the transformation, the solution has to cooled down even more.
Freezing point and molality concentration is related by
[tex]\Delta T=T_{f}_{(solvent)}-T_{f}_{(solution)}=K_{f}.m[/tex]
where
ΔT is freezing point depression
[tex]T_{f}_{(solvent)}[/tex] and [tex]T_{f}_{(solution)}[/tex] are freezing point of solvent and solution, respectively
[tex]K_{f}[/tex] is freezing point depression constant
m is molality concentration
Dibenzyl ether is the solvent and has the following properties: [tex]K_{f}=[/tex] 6.27 and [tex]T_{f}[/tex] = 3.6°C.
Molality concentration is
[tex]m=\frac{T_{(solvent)}-T_{(solution)}}{K_{f}}[/tex]
[tex]m=\frac{3.6-1}{6.27}[/tex]
m = 0.415
Molality concentration is moles (n) of solute dissolved in a mass, in kilogram, of solvent.
[tex]m=\frac{moles}{mass(kg)}[/tex]
n = m(mass of solvent in kg)
n = 0.415(0.035)
n = 0.0145
Molar mass (M) is the weight of one sample mole and can be calculated as
[tex]n=\frac{m}{M}[/tex]
M = [tex]\frac{m}{n}[/tex]
m in grams
Molar mass of compound X is
[tex]M=\frac{0.24}{0.0145}[/tex]
M = 16.55
Molar mass of molecular compound X is 16.55g/mol
Which terms describe a substance that has a low melting point and poor electrical conductivity?
(1) Metallic and lustrous
(2) Dull and brittle
(3) Brittle and lustrous
(4) Metallic and dull
HELP ASAPPPP BRAINLIEST
Answer:
2nd option
Explanation:
Argon (Ar) is an element in group 18. Argon is _____.
a gas highly reactive
a metalloid
a good conductor of heat
Answer:
c
Explanation:c
it is a good conducter
Which reaction takes place in a nuclear fission reactor?
C+HN
2 Put He → Cm
OCO+ He-Cot 'n
o U+ nKr+Ba+3'n
Answer:
The reaction that takes place in a nuclear fission reactor is answer D.
Explanation:
Step-by-step explanation:
Nuclear fission reactions involves the process by which large atomic nuclei are bombarded with energetic particles and release of an enormous amount of nuclear energy, which mainly ends up as heat energy.
So now, consider the nuclear reaction from D, after the uranium nucleus absorbs the neutron its split into two smaller nuclei (often radioactive themselves), Krypton and Barium and releases more neutrons (or energy).
Someone took the last cookie from the cookie jar last night. The last person to leave the scene is the culprit. Who was it? Highlight the guilty culprit based on the clues provided.
Need help with this please thanks
Answer: 1. [tex]2H_2+O_2\rightarrow 2H_2O[/tex]
2. [tex]P_4+3O_2\rightarrow 2P_2O_3[/tex]
3. [tex]N_2+3H_2\rightarrow 2NH_3[/tex]
4. [tex]2K+Cl_2\rightarrow 2KCl[/tex]
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The given equations are balanced as:
1. [tex]2H_2+O_2\rightarrow 2H_2O[/tex]
2. [tex]P_4+3O_2\rightarrow 2P_2O_3[/tex]
3. [tex]N_2+3H_2\rightarrow 2NH_3[/tex]
4. [tex]2K+Cl_2\rightarrow 2KCl[/tex]
which two changes of state can be caused by removing thermal energy from a substace A. deposition B. condencation C. vaporization D.sublimation
Answer:
maybe is b but wait to other people answer
Answer:A. deposition B. condencation
Explanation:
Help! I dont know how to do this lol
the order is :
- Aufbau principle
- Hund's Rule
- Pauli's Exclusion Principle
What happens after condensation to cause precipitation?
A
The sun heats water on the Earth's surface.
B
Water is absorbed into the ground.
C
Clouds fill with moisture and get too heavy.
D
Excess water runs downhill.
Answer:
The answer is c, Clouds fill with moisture and get too hravy
1 carbon atom mixed with 1 oxygen atom what is the formula
Answer:
carbon mono oxide CO
Explanation:
as both are in 1:1 ratio so CO is formed
What is the structural formula of CF2Br2
Answer:
Dibromodifluoromethane
Explanation:
A compound is an example of pure substance
True
False
Justin is making a snack. He toasts a piece of bread and first peanut butter and jelly on it. Then he cut an apple into several slices and adds these to his plate. Next Justin mixes a scoop of lemonade powder into a glass of water mixes it in Dad's ice. How many chemical changes occurred in this scenario? 1 2 three or four
Answer:
2
Explanation:
Toasting bread and lemonade powder in water are chemical changes. Pb&j on bread and cutting apple are physical changes.
Answer:
b
Explanation:
Which of the following statements is true?
Electrons have a positive charge.
Protons and neutrons are found in the nucleus.
Electrons and protons are found in the nucleus.
All shells can hold up to eight electrons.
Answer:
2/ Protons and neutrons are found in the nucleus.
Explanation:
Which set of terms best defines what affects kinetic energy and potential energy, respecrively
Why are a molecule's atoms as far away from each other as they can get?
A) Electronegativity differences force the atoms apart
B) The protons in the nuclei push the atoms apart
C) Forces between electron pairs push the atoms apart
D) Induced dipoles push the atoms away from each other
Answer:
the answer is a
Explanation:
an electron contains a negative charge and like charges repel each other. Hence, in a atom the force of repulsion between the atoms away from each other. As a result a molecules atoms are as far away from each others as they can get .
A molecule's atoms as far away from each other as they can get because "Forces between electron pairs push the atoms apart".
So, option C is correct one.
Why electrons repel each other?Since, an electron is negative charge species revolve around the nucleus of an atom. So, when two atoms come close to each other in molecules there is repulsion occurs between negative charge electron .
To learn more about electrons here.
https://brainly.com/question/18367541
#SPJ3
15 points! Answer only if you can please!
1. Have you ever grabbed the handle of a hot metal pan? Why did it feel hot to you?
2. What would happen if a person who is wearing a heavy winter jacket were to place a thermometer inside the jacket next to his or her skin? What would happen if we took the same jacket, after it had been hanging in a closet, and placed a thermometer inside?
3. How do you think the transfer of thermal energy causes unpopped popcorn kernels to pop?
Answer:
1. Yes
2. it would be the same i guess
3. because it travels to popcorn kernels with its heat and makes it pop'
did i get it right?
Explanation:
Explain how atoms organize to create larger structures?
Answer:
First of all they are super tiny particles of neutrons, electrons and protons. Then they come together to organize a structure of atom. Atoms come together to form a molecule and smaller molecules work together to form macromolecules. Thus, how they organize and form building blocks of a substance.
Hope it helps!<3
What is a solute?
A material that is dissolved in another material.
O A material in which another material is dissolved.
An area of space surrounding the nucleus.
O Chemical formulas on the left side of an equation.
Which isomer of 1-bromo-2-tert-butylcyclohexane reacts faster when refluxed with potassium tert-butoxide?Draw the structure of the expected major product from the faster reacting compound.
Answer:
See explanation and image attached
Explanation:
The reaction of 1-bromo-2-tert-butylcyclohexane with potassium tert-butoxide is an elimination reaction that occurs by E2 mechanism.
The E2 reaction proceeds faster when the hydrogens are in an antiperiplanar position at an angle of 180 degrees.
This is only attainable in the trans isomer of 1-bromo-2-tert-butylcyclohexane. Hence trans 1-bromo-2-tert-butylcyclohexane reacts faster with potassium tert-butoxide
what is protein denaturation
Answer:
Denaturation is a process in which proteins or nucleic acids lose the quaternary structure, tertiary structure, and secondary structure which is present in their native state, by application of some
Explanation:
Two isotopes of hypothetical element X exist with abundances of 30.00% 100X and 70.00% 101X. What is the approximate atomic mass of X (in atomic units, amu)?
(A) 100.3
(B) 100.5
(C) 100.7
(D) 101.0
Answer:
C. 100.7 amu
Explanation:
Isotopes of an element are atoms of an element with the same atomic number but different atomic masses. Each atomic mass of an isotope is known as an isotopic mass. An element that exhibits isotope, that is, that have two or more isotopes has a relative atomic mass that is not a whole number.
Relative atomic mass of X is the sum of the products of the relative abundances of each isotope and its isotopic mass.
For Isotope ¹⁰⁰X: 30% × 100 = 30 amu
For Isotope ¹⁰¹X: 70% × 101 = 70.7 amu
Relative atomic mass of X = (30 + 70.7) amu = 100.7 amu
Therefore, the approximate atomic mass of X is 100.7 amu
Taking into account the definition of mass number, isotopes and atomic mass of an element, the average mass of hypothetical element X is 100.7.
First of all, all atoms are made up of subatomic particles: protons and neutrons, which are part of their nucleus, and electrons, which revolve around them. Protons are positively charged, neutrons are neutrally charged, and electrons are negatively charged (electrons).
On the other hand, the mass number tells us the total number of particles in the nucleus. That is, the mass number is the sum of the number of protons and the number of neutrons in the atomic nucleus.
The same chemical element can be made up of different atoms, that is, their atomic numbers are the same, but the number of neutrons is different. These atoms are called isotopes of the element.
Finally, the atomic mass of an element is the weighted average mass of its natural isotopes.
In other words, the atomic masses of chemical elements are usually calculated as the weighted average of the masses of the different isotopes of each element, taking into account the relative abundance of each of them.
In this case, two isotopes of hypothetical element X exist with abundances of 30.00% 100-X (the atomic mass is 100) and 70.00% 101-X (the atomic mass is 101). Then, the average mass of X can be calculated as:
100×0.30 + 101×0.70= 100.7
Finally, the average mass of hypothetical element X is 100.7.
Learn more about average mass:
brainly.com/question/14403750?referrer=searchResults brainly.com/question/10043246?referrer=searchResults brainly.com/question/15553207?referrer=searchResultsThe reaction between calcium carbonate (CaCO3) and HCl produces calcium chloride (CaCl2), carbon dioxide (CO2), and water (H2O).What happens when the concentration of hydrogen chloride (HCl) molecules is doubled in this reaction?
CaCO3 + 2HCl → CaCl2 + CO2 + H2O
Answer:
yes that is right
Explanation:
Answer: what is the answer im on plato
Explanation: