Answer: An exothermic reaction is a "reaction for which the overall standard enthalpy change ΔH⚬ is negative." Exothermic reactions usually release heat and entail the replacement of weak bonds with stronger ones.
Exothermic reactions are important to forensic sciences and particularly to fire and explosion investigation. When a chemical reaction requires heat (rather than producing it) and results in cooling down the surroundings, it is conversely called endothermic.
Example-
Respiration is a series of exothermic reactions that occur in the mitochondria of living cells in order to release energy from food molecules. This energy can then be used to produce heat, for movement, growth, reproduction and active uptake.
Hope it helps
Classify Sr(OH)2 as a strong
base or a weak base.
Strong Base or Weak Base
this is a strong base and is one of the many bases that you're required to memorize.
What are differences between viruses and bacteria?
Answer:
viruses are computer program that replicate itself and distribute itself to another computer but bacteria is micro organism that contaminate our food and can make us sick
lanthanides and actinides are kept separately in the periodic table. why?
differentiate between Physical and chemical changes
Answer:
In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.
I HOPE THIS WILL HELP YOU IF NOT THEN SORRY HAVE A GREAT DAY:)Which statement best describes the destiny of an atoms nucleus?
Answer:
The answer would be: An atom’s nucleus occupies very little of the atom’s volume but contains most of its mass
Explanation:
The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom.
Almost all of the mass of an atom is located in the nucleus, with a very small contribution from the electron cloud.
Refer to https://en.wikipedia.org/wiki/Atomic_nucleus for further understanding
How would you upscale your chemistry learning through
the knowledge of periodic table. Explain? (5 marks worth answer)
Explanation:
The periodic table brings order to information about the chemical elements. It helps chemists to understand why elements react as they do. Elements in the same group have similar chemical properties. This is because they have the same number of outer electrons and the same valency
Hòa tan hoàn toàn 10 gam hỗn hợp hai oxit CuO và Fe2O3 cần 100ml dung dịch HCl 3,5M. Khối lượng CuO và Fe2O3 có trong hỗn hợp ban đầu lần lượt là
Answer:
CuO+2HCl>h2o+CuCl2
fe203+6hcl->2fecl3+3h2O
gọi CuO, fe2o3 lần lượt là x,y
80x+160y=10
2x+6y=0.35
giải phương trình ta dc hai số x,y(tính phương trình kia ra)
cuo ban đầu sẽ là :60*x=z
fe203 ban đầu sẽ là :10-z=
Explanation:
Tìm hóa trị của Fe trong hợp chất : FESO4, FE2(SO4)3, FR(OH)2, FE(OH)3
Answer: Fe hóa trị II trong các hợp chất: FeSO4, Fe(OH)2
Fe hóa trị III trong các hợp chất: Fe2(SO4)3, Fe(OH)3
Explanation:
What is an atomic mass unti
Explanation:
a unit of mass used to express atomic and molecular weights, equal to one twelfth of the mass of an atom of carbon-12.
Answer:
Atomic Mass Unit is also called Dalton. It is used to express atomic and molecular weight. It is defined as 1/12 of the mass of an unbound neutral atom of carbon.
The lattice energy for an ionic compound cannot be measured directly but can be calculated from the Born-_____ cycle, using a series of individual steps for which all enthalpies are known except for the lattice energy. This method is an application of Hess's law which, states that the overall energy change for a process is given by the _____ of the enthalpy changes for the individual steps.
Answer:
first is HABER
second is SUM
Explanation:
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What is the [H+] if the pH of a solution is 3.20?
(in scientific notation)
Answer:
[H⁺] = [tex]6.3096[/tex]×[tex]10^{-4}[/tex] M
Explanation:
pH= - log[H⁺]
=> 3.2 = - log[H⁺]
=> [H⁺] = [tex]10^{-3.2}[/tex]
∴ [H⁺] = [tex]6.3096[/tex]×[tex]10^{-4}[/tex] M
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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 meant by the term "boiling point of water"
Answer:
boiling point, temperature at which the pressure exerted by the surroundings upon a liquid is equaled by the pressure exerted by the vapour of the liquid; under this condition, addition of heat results in the transformation of the liquid into its vapour without raising the temperature
in case of water boiling point bring 0 degree
Answer:
it is the temperature at which water starts to boil. the temperate is 100°C or 212°F
In what form is radiation emitted from the earth's surface
back into the atmosphere?
Answer:
thermal radiation
Explanation:
Outgoing Long-wave Radiation (OLR) is electromagnetic radiation of wavelengths from 3–100 μm emitted from Earth and its atmosphere out to space in the form of thermal radiation. It is also referred to as up-welling long-wave radiation and terrestrial long-wave flux, among others.
Which of the following is the best definition of ethics?
A. The maintenance of a stable internal environment
B. Response to external stimuli
C. A set of guidelines for fair conduct during an experiment
D. A multistep process whose last step controls what happens in an
earlier step
Answer:
C
Explanation:
I believe the answer is C.
Use the periodic table to identify the element indicated by each electron configuration by typing in the chemical symbol for the element.
1s22s22p6:
A small gap in skit in railway track why
Answer:
To reduce the bending of the railway
Explanation:
During summer(heat) metals tend to expand in size. The skits/gaps are present in the railway so that the metal could expand without causing bending of the railway track.
what is a cubic unit cell ?
cubic unit cell is the smallest repeated unit which have all angles equal to 90 and all have edge lengths equal
It is the type of the Unit cell which is having all angles equal to 90 and all sides equal to each other
it's is a unit cell with cubic structure
What are three ways that plastic pollution is harmful on land
Answer:
Plastic pollution are harmful on land because;
It can make human felt sick which is not healthy for us.Does the following word describe a theory, law, or both
“Simple”
A) LAW
B) THEORY
C) BOTH THEORY AND LAW
Answer:
B
Explanation:
I would say theory since a law is already set and proven by evidence. Theories arent necessarily proven.
A chemist determines by measurements that 0.0550 moles of nitrogen gas participate in a chemical reaction. Calculate the mass of nitrogen gas that participates.
Be sure your answer has the correct number of significant digits.
The mass of nitrogen gas that participated in the chemical reaction is 1.54g
HOW TO CALCULATE MASS OF AN ELEMENT:
Mass of a substance can be calculated by multiplying the number of moles in mol of the substance by its molecular mass in g/mol. That is;mass (M) = molar mass (MM) × number of moles (n)According to this question, a chemist determines by measurements that 0.0550 moles of nitrogen gas (N2) participate in a chemical reaction.
The molecular mass of nitrogen gas (N2) = 14.01(2)= 28.02g/mol
Hence, the mass of the nitrogen gas that participated in the chemical reaction is calculated as follows:
Mass (g) = 0.0550 mol × 28.02 g/molMass = 1.5411Therefore, the mass of nitrogen gas that participated in the chemical reaction is 1.54g
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Which natural resource is renewable?
coal
wind
topsoil
O oil
An example of natural resource that is renewable is wind. Details about natural resources can be found below.
What is natural resources?Natural resources are resources that cannot be exhausted i.e. can be replenished with time.
Examples of natural resources are as follows:
SunWindWaterForest treesTherefore, an example of natural resource that is renewable is wind.
Learn more about natural resources at: https://brainly.com/question/15211198
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The natural resource that is renewable is wind. Therefore, option B is correct.
What are renewable resources?Renewable resources are natural resources that can be restocked or regenerated over a relatively short period of time, usually within a human lifetime. These resources are often contrasted with non-renewable resources, such as fossil fuels, which take millions of years to form and are finite in quantity.
Examples of renewable resources include solar energy, wind energy, hydroelectric power, geothermal energy, biomass, and tidal power.
These resources have the potential to provide energy and other materials indefinitely if used sustainably, making them an important part of efforts to move towards a more sustainable future. Therefore, option B is correct.
Learn more about renewable resources, here:
https://brainly.com/question/19604560
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A fixed mass of gas has a volume of 92 cm cube and 3 degrees Celsius. What will be its volume at 18 degrees celsius if the pressure remains constant?
Answer:
94.8454
Explanation:
Let volume be V
Let Temperature be T
V1= 92
T1= 3C but to kelvin 273+3= 300K
V2= ?
T2= 18 C but to kelvin 18+273= 291
[tex] \frac{v1}{t1} = \frac{v2}{t2} [/tex]
[tex] \frac{92}{300} = \frac{v2}{291} [/tex]
[tex]v2 \times 300 = 92 \times 291[/tex]
[tex]v2 = \frac{92 \times 291}{300} [/tex]
[tex]v2 = 94.8454[/tex]
What is the pH of a 2.50×10^-4 M solution of sodium hydroxide
Answer:
Answer is 10.398(approx.)
Explanation:
NaOH ⇄ Na⁺ + OH⁻
pOH = -log[OH⁻]= -log(2.5×10⁻⁴) = 3.602
∴pH = 14 - pOH = 10.3989(approx.)
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career in chemistry list ten
Answer:
Analytical Chemist
Forensics
Toxicologist
Biochemist
Chemical Engineer
Laboratory Technician
Pharmacologist
Chemical Technician
Materials Scientist
Environmental Chemist
Use Charles's Law to solve the following problem. A sample of air has a volume of 550.0 mL at 106 °C. At what temperature will its volume be 700.0 mL at constant pressure?
a
482 K
b
63 °C
c
505 K
d
119 °C
Answer:
im not sure but i think its c
505 K
Can someone help me pls
What do you think nowadays computer engineer, civil engineer or electrical engineer which one is more demanded?
balance this equation
PB3 O4 + H2 → PB + H2O
Answer:
Pb3O4 + 4H2 → 3Pb + 4H2O
Explanation:
Pb3O4
Tritium - H2
Molar Mass of H2 Bond Polarity H-3 Hydrogen-3 3H T
Products
Lead - Pb
Molar Mass of Pb Plumbum Element 82 Bulk Lead
Water - H2O
Molar Mass of H2O Oxidation Numbers of H2O Dihydrogen Monoxide Dihydridooxygen Hoh Hydrogen Hydroxide Dihydrogen Oxide Oxidane Hydrogen Oxide Pure Water
Volume = 90g / 3g cm3 What is the volume help ASAP
Answer:
The answer will be this 30g/cm3
The world is made up of
Answer:
Explanation:
The world is made up of living beings .
