Answer:
Concept of chemi-fluorescence
Explanation:
A glow stick usually consists of two chemicals in a larger plastic tube: , a base catalyst (mostly sodium salicylate), and a suitable dye (sensitizer, or fluorophor). This creates an exergonic reaction when mixed together.
When a glow stick is bent, the flurophor which is a chemical that easily re-emits light upon excitation in smaller capsules is released into the other substance, there by causing it to emit radiation/light in the uv-visible region. The brightness and longevity of the glow stick is determined by varying the concentration of these chemicals.
I hope this explanation clarifies things.
Julie finds a snail on the sidewalk and wants to know whether or not the snail moves throughout the day. She places a
single mark on the sidewalk next to the snail.
What will Julie use the mark for initially?
determining how fast the snail moves
acting as a standard unit of measure
determining the displacement of the snail
O acting as a reference point for detecting motion
The single mark placed on the sidewalk by Julie has been acting as the reference point for detecting the motion of the snail. Thus, option D is correct.
The snail has been the shelled animal that has been mostly residing in the resting condition with limited movement. To evaluate the movement of the snail, there has been the consideration of a point that was the starting point from the movement.
The line that has been set across the sidewalk has been acting as the reference, and the distance traveled has been calculated from that point. Thus, option D is correct.
For more information about the reference point, refer to the link:
https://brainly.com/question/1674904
Cuantos gramos de sulfato de plomo (II) se requieren para preparar 200mL una solución de esta sal a una concentración de 100 ppm. Si se toma una muestra de 30 mL de la disolución anterior y se diluye en 1000 mL de agua, ¿cuál es la concentración de la disolución?
Answer:
0.020g de sulfato de plomo se requieren
La concentración de la solución diluida es de 3ppm
Explanation:
Las partes por millón (ppm) son definidas como:
miligramos soluto / 1L solución.
Si deseas preparar una solución a 100ppm de sulfato de plomo (II) necesitas 100mg de este sulfato en 1L. En 200mL = 0.200L vas a necesitar:
0.200L × (100mg / 1L) = 20mg de sulfato de plomo (II).
Como 1000mg = 1g,
20mg × (1g / 1000mg) = 0.020g de sulfato de plomo se requieren.
Ahora, se van a tomar 30mL de esta solución y se diluirán a 1000mL. Se diluye la solución:
1000mL / 30mL = 33.33 veces.
Como la solución inicial es de 100ppm, esta dilución genera una solución de concentración:
100ppm / 33.33 = 3ppm
May I know how to balance this
Answer:
C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O
Explanation:
Let's start by counting how many molecules we have on each side.
Reactants
C - 5
H - 12
O - 2
Products
C - 1
O - 3
H - 2
We have to balance both sides. Since we have 5 carbon atoms on the reactants side and 1 carbon atom on the products side, we'll start with that. Write 5 as the coefficient for CO₂ to balance the carbons.
C₅H₁₂ + O₂ → 5CO₂ + H₂O
Now that the carbons are balanced, let's look at the hydrogens. There's 12 on the reactants side and 2 on the products side. To balance the hydrogens, we have to write 6 as the coefficient for H₂O.
C₅H₁₂ + O₂ → 5CO₂ + 6H₂O
Now the hydrogens are balanced. All that's left to do is balance the oxygens. Let's start by counting how many atoms we have on each side.
Reactants
C - 5
H - 12
O - 2
Products
C - 5
H - 12
O - 16
So, to balance the number of atoms on both sides, write 8 as the coefficient for O₂.
C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O
Lastly, let's check to make sure everything is balanced.
Reactants
C - 5
H - 12
O - 16
Products
C - 5
O - 16
H - 12
Both sides are balanced. Therefore, the balanced chemical equation is: C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O.
Hope that helps.
Answer:
[tex]\boxed{C_{5}H_{12} + 8O_{2} -->5CO_{2} + 6H_{2}O}[/tex]
Explanation:
Part 1: Count the number of atoms on each side per element
To start, count the number of atoms per element on both sides of the equation.
Left Side
C - 5 atoms
H - 12 atoms
O - 2 atoms
Right Side
C - 1 atom
H - 2 atoms
O - 3 atoms
Part 2: Balance carbon atoms
Now, with this information, you can begin finding out how to properly balance both sides of the equation.
You need 5 carbon atoms on the left, so place a coefficient of 5 in front of the [tex]CO_{2}[/tex] product. This will balance the carbons. Do not place a coefficient in front of the [tex]C_{5}H_{12}[/tex] reactant - none are necessary!
Then, you can update your counts for your atoms.
Left Side
C - 5 atoms
H - 12 atoms
O - 2 atoms
Right Side
C - 5 atoms
H - 2 atoms
O - 11 atoms
The updated equation will look like this:
[tex]\boxed{C_{5}H_{12}+O_{2} --> 5CO_{2} + H_{2}O}[/tex]
Part 3: Balance hydrogen atoms
Now, balance the hydrogen atoms. Place a coefficient of 6 in front of the [tex]H_{2}O[/tex] product. This will balance the hydrogen atoms.
Once again, update the atom counts:
Left Side
C - 5 atoms
H - 12 atoms
O - 2 atoms
Right Side
C - 5 atoms
H - 12 atoms
O - 16 atoms
The updated equation will look like this:
[tex]\boxed{C_{5}H_{12} +O_{2}--> 5CO_{2} +6H_{2}O}[/tex]
Part 4: Balance oxygen atoms
To fully balance the equation, place a coefficient of 8 in front of the [tex]O_{2}[/tex] reactant. This will equalize the amount of oxygen atoms on both sides of the equation.
The updated equation will look like this:
[tex]\boxed{C_{5}H_{12} + 8O_{2} --> 5CO_{2} + 6H_{2}O}[/tex]
Part 5: Check the equation and atom counts
Now, update the atom counts one last time to make sure they are equal.
Left Side
C - 5 atoms
H - 12 atoms
O - 16 atoms
Right Side
C - 5 atoms
H - 12 atoms
O - 6 atoms
They are equal, so you may proceed.
Part 6: Check if reductions are necessary
If the equations coefficients can all be divided by a common divisor (i.e., 3), follow up with that step. However, any equation that has a reactant or product without a coefficient, skip this step entirely.
This equation falls into that category, so you may proceed past it.
Your final equation will look like this: [tex]\boxed{C_{5}H_{12} + 8O_{2} -->5CO_{2} + 6H_{2}O}[/tex]
Determine the rate of a reaction that follows the rate law: rate = k[A]^m[B]^n, where: k = 0.2, [A] = 3 M, [B] = 3 M, m = 1, n = 2 A. 1.2 (mol/L)/s B. 27 C. 1.8 D. 5.4
[tex]7.408 \;X 10 ^ {-3} m^{-2} s^{-1}[/tex] is rate of a reaction when k = 0.2, [A] = 3 M, [B] = 3 M, m = 1, n = 2 .
What is the rate of a reaction?The rate at which the concentration of reactant or product participating in a chemical reaction alters is called the rate of reaction.
Rate of reaction = [tex]\frac{change \;in \;concentration}{time}[/tex] = (mol/litre)/time.
m= 1 and n = 2
[tex]rate = K [A] [B]^2[/tex]
[tex]0.2 = K X 3 X 3 ^2[/tex]
K = [tex]\frac{0.2 }{27 }[/tex]
K = [tex]7.408 \;X 10 ^ {-3} m^{-2} s^{-1}[/tex]
Hence, [tex]7.408 \;X 10 ^ {-3} m^{-2} s^{-1}[/tex] is rate of a reaction when k = 0.2, [A] = 3 M, [B] = 3 M, m = 1, n = 2 .
Learn more about the rate of a reaction here:
https://brainly.com/question/8592296
#SPJ2
Answer: 7.4 10-3
Explanation:
7.4 10-3 this is right ong
Acetic acid only partially ionizes in water. A solution contains a large quantity of acetic acid dissolved in water. How can this acid solution best be described?
Answer:
The acid solution is a concentrated solution.
Explanation:
Acetic acid is a weak acid, because it ionizes partially in water as shown below:
CH3COOH + H2O —> H3O+ + CH3COO-
A solution containing a larger quantity of acetic acid is termed concentrated solution.
This is so because a concentrated solution is a solution that contains more of the solute than the solvent.
A solute is the substance which dissolves in the solvent.
A solvent is the substance which dissolves a solute.
In this case, acetic acid is the solute and water is the solvent.
Solution is simply the combination of solute and solvent
Solution => Solute + Solvent
More solute + Less solvent => Concentrated solution
Therefore, a solution containing a higher quantity of acetic acid ( i.e the solute) in water (i.e the solvent) is called a concentrated solution.
Research on ‘where a person’s carbon emissions come from inside a home’ and represent the data in the form of a pie chart. Pls answer with pie chart I WILL MARK U AS BRAINSLIEST IF YOU GIVE RIGHT ANSWER
Answer:
Here's what I get from one source.
Explanation:
[tex]\begin{array}{lc}\textbf{Source} &\textbf{Contribution \%} \\\text{Space heating }& 45\\\text{Water heating} &18\\\text{Space cooling} & 9 \\\text{Computers/Electronics} & 6 \\\text{Lighting} & 6 \\\text{Cooking} & 4 \\\text{Refrigeration} & 4 \\\text{Wet cleaning} & 3 \\\text{Other} & 5 \\\end{array}[/tex]
The pie chart is in the Figure below.
What does the pH of a solution have to be in order to be a base?
Explanation:
pH is used to measure the concentration of H+ ions ([H+]) and therefore, whether a substance is acidic or basic (alkaline). Solutions with a pH of less than seven are acidic, while those with a pH greater than seven are basic (alkaline).
Answer:
greater than 7
Explanation:
A base is any solution with a pH greater than 7. A pH of 7 is considered neutral. For example, the pH of water. An acid is any solution with a pH less than 7.
Hope that helps.
The radioactive isotope used for carbon dating is
1. Carbon 12
2. Carbon 13
3. Carbon 15
4. Carbon 14
Carbon 14 would be your answer, however if it's more than one answer it would also be Carbon 12, so yeah. Your best bet would be Carbon 14.
which of the following would be an appropriate situation for you to use the eye wash station
Answer:
if your eyes are exposed to a hazardous chemical you should use the eye wash station. The first few seconds after exposure to a hazardous chemical are critical.
Which statement describes an electron?
Answer:
The statement that describes an electron is "It has a negative charge and is located in orbitals around the nucleus." Electrons are the smallest of the three particles that make up atoms
Explanation:
Electrons are found in shells or orbitals that surround the nucleus of an atom
Electrons are the sub-atomic particles that carry a negative charge over them. In the atom, the electrons are found in the orbitals or the shells around the nucleus. Thus, option D is correct.
What are electrons?
Electrons are the smallest sub-atomic particle that has been known to carry a negative charge and are found in the orbitals of the atom. The charge carried by an electron is 1.602 x 10⁻¹⁹ coulomb and is small than the proton and neutron.
They revolve around the nucleus in their orbits and exhibit the properties of waves and matter. The number of electrons and protons are the same in a neutral atom which makes the atomic number.
Therefore, the electrons have been known to carry a negative charge that revolves in orbit around the nucleus.
Learn more about electrons here:
https://brainly.com/question/11670765
#SPJ6
Your question is incomplete, but most probably your full question was, Which statement describes an electron?
It has a positive charge and is located in the nucleus. It has a positive charge and is located in orbitals around the nucleus. It has a negative charge and is located in the nucleus. It has a negative charge and is located in orbitals around the nucleus The intake stroke of a positive displacement compressor is most similar to that of a
A. thermostatic expansion valve.
B. auxillary electric water pump.
C. one-stroke variable displacement compressor.
D. two-stroke cylinder engine.
Answer:
D. two-stroke cylinder engine.
Explanation:
Two-stroke cylinder engine: In chemistry, the term "two-stroke cylinder engine" is described as one of the types of "internal combustion engine" that tends to complete a single "power cycle" possessing two different strokes of the "piston" during a particular "crankshaft revolution".
It generally consists of two different strokes that are being often known as power or exhaust and suction stroke.
In the question above, the given statement signifies the "two-stroke cylinder engine".
What are chemical changes of matter?
Answer:
Chemical Changes are also called Chemical Reactions. Chemical reactions involve combining different substances. The chemical reaction produces a new substance with new and different physical and chemical properties. Matter is never destroyed or created in chemical reactions.
Explanation:
Which of these is an example of something a civil engineer would deal with?
A. The rebuilding and redesign of the dam in Louisiana after
Hurricane Katrina
B. A gauge that reads the strength of an earthquake
C. The new hybrid cars that are more environmentally friendly and
reduce oil consumption
D. The design of the Discovery space shuttle
Answer:
A
Explanation:
civil deals with desighning, construction work of natural or physical environment and a fits guess
The equilibrium concentrations for the reaction between SO2 and O2 to form SO3 at a certain temperature are given in the table below. Determine the equilibrium constant and whether the reaction favors reactants, products, or neither at this temperature.
Answer:
Option B. K = 1.3×10⁴, product favored
Explanation:
Data obtained from the question include:
O2(g) + 2SO2(g) <==> 2SO3(g)
Concentration of O2, [O2] = 0.024 M
Concentration of SO2, [SO2] = 0.015 M
Concentration of SO3, [SO3] = 0.26 M
Equilibrium constant, K =..?
The equilibrium constant, K is simply defined as the ratio of the concentration of products raised to their coefficient to the concentration of the reactants raised to their coefficient.
The equilibrium constant for the above reaction can be written as
K = [SO3]² / [O2] [SO2]²
Inputing the values of [SO3], [O2] and [SO2] the equilibrium constant, K is:
K = [SO3]² / [O2] [SO2]²
K = 0.26² / 0.024 × 0.015²
K = 1.3×10⁴
Therefore, the equilibrium constant K is 1.3×10⁴.
Since the value of the equilibrium constant, K is large and positive, therefore, the reaction favours the product.
Describe how red shifts were used by cosmologists to determine that the universe was expanding. How
is this evidence for the big bang theory?
Explanation:
astronomers have discover that in general the future of a Galaxy is, the more redshift light is this mean that the further away the Galaxy are the faster they are moving this is similar to explosion where the bits moving fastest travel for furthest on the explosion redshift data provides evidence that the universe including space itself is expanding .
144g of KCl dissolved in 1000cm3of water at 90oC. Calculate the solubility of KCl at this temperature. (K=39, Cl=35.5, 1dm3=1000cm3).
Answer:
The solubility of KCl is 1.93 mol/dm³
Explanation:
The information given are;
The mass of the potassium chloride, KCl = 144 g
The volume of the water solvent = 1000 cm³ = 1 dm³
The temperature of the solvent = 90 °C
The atomic mass of potassium, K = 39 u
The atomic mass of chlorine, Cl = 35.5 u
The number of moles of potassium in one mole of potassium chloride, KCl = 1 mole
The number of moles of chlorine in one mole of potassium chloride, KCl = 1 mole
The molar mass of the potassium chloride = 39 + 35.5 = 74.5 g/mol
The number of moles, n, of potassium chloride, KCl in 144 g of potassium chloride, KCl is given as follows
n = Mass/(Molar mass) = 144/74.5 = 1.93 moles
1.93 moles will dissolve in 1 dm³
Therefore, the solubility of KCl is 1.93 mol/dm³.
The table shows the conditions during two trials of a reaction.
Answer:
The correct option is;
The reaction pathway for the trials is different
Explanation:
The effect of a catalyst in a chemical reaction is to increase the rate of a reaction by changing the pathway or mechanism of the reaction and/or to lower the transition state's energy thereby lowering the activation energy of the reaction
The pathway of the reaction is changed by the catalyst by the formation of intermediate compounds by the catalyst which require lower activation energy to form the products than the original non-catalyzed reactants. In the process the catalyst is regenerated, thereby, not taking part in the reaction.
Which sequence represents the relationship between temperature and volume as explained by the kinetic-molecular
theory?
higher temperature - more kinetic energy - more space between particles - higher volume
higher temperature-less kinetic energy less space between particles - higher volume
higher temperature → more kinetic energy less space between particles > lower volume
higher temperature-less kinetic energy → more space between particles lower volume
3
and wit
Answer:
A.
Explanation:
Higher temperature - more kinetic energy - more space between particles - higher volume.
what is a chemical bond? an attractive force between 2 molecules
Answer:
The chemical bond between 2 molecules is called an intermolecular force.
Answer:
Chemical Bond:
Attraction between two atoms results in the formation of a bond which is called a chemical bond.
Inter molecular Forces:
Attractive Force that in between 2 molecules is called Inter molecular Forces. (Inter : Between)
An ionic bond is the attraction between _____.
Answer:
oppositely charged ions in a chemical compound
Explanation:
Answer:
Between ions
Explanation:
which one of the following electronic configuration represents the element that forms simple ion with a charge of-3? (a)1s^2,2s^2,2p^6,3s^2,3p^1 (b)1s^2,2s^2,2p^6,3s^2,3p^3 (c)1s^2,2s^2,2p^6,3s^2,3p^6,3d^1,4s^2 (d)1s^2,2s^2,2p^6,3s^2,3p^6
Answer:
(b)
Explanation:
The 3s^2, 3p^6 orbitals form -3 charge.
This is the element phosphorous and an example of a -3 ion is in aluminium phosphide, AlP3.
The electronic configuration which represents the element forming a simple ion having with a charge of -3 is; 1s², 2s², 2p⁶, 3s², 3p³. Option B is correct.
In this electronic configuration, the element has a total of 16 electrons. To form a simple ion with a charge of -3, the element needs to gain three electrons. This is achieved by adding three extra electrons to the existing configuration.
When the element gains three electrons, the electron configuration becomes:
1s², 2s², 2p⁶, 3s², 3p⁶
This configuration represents the stable octet configuration, where the element has a complete outer shell with eight electrons. Since the charge is -3, it means the element has gained three extra electrons to achieve a stable configuration.
Therefore, the correct electronic configuration representing the element that forms a simple ion with a charge of -3 is 1s², 2s², 2p⁶, 3s², 3p³
Hence, B. is the correct option.
To know more about electronic configuration here
https://brainly.com/question/29184975
#SPJ2
Which of the following is an aldehyde?
Answer: [tex]CH_3CH_2CH_2CHO[/tex] has aldehyde functional group.
Explanation:
Functional groups are specific group of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules.
A. [tex]CH_3CH_2CH_2COCH_3[/tex] has ketone [tex]C=O[/tex] functional group .
B. [tex]CH_3CH_2CH_2COOH[/tex] has carboxylic acid [tex]COOH[/tex] functional group .
C. [tex]CH_3CH_2CH_2CHO[/tex] has aldehyde [tex]H-C=O[/tex] functional group .
D. [tex]CH_3CH_2CH_2COOCH_3[/tex] has ester [tex]RO-C=O[/tex] functional group .
Thus [tex]CH_3CH_2CH_2CHO[/tex] has aldehyde (CHO) group.
What evidence suggests that global climate change is causing the oceans to get warmer?
Answer:
A large point of evidence in this would be the rate of increase in how fast the polar ice caps are melting and the ocean is rising as a result. As the climate is getting warmer so are the oceans and this is causing the ice caps which are in the ocean.
Explanation:
calculate the mass of sodium sulphate required to prepare its 20%of solution in 100 g ofwater
Answer:
25 g
Explanation:
Mass percent implies the mass of solute dissolved in a solution
Mass percent = mass of solute/mass of solute + mass of solvent × 100/1
Since mass percent concentration= 20%
Mass of solvent = 100g
Let mass of solute = x
Hence;
20 = x/x +100 ×100/1
20/100= x/x + 100
0.2 = x/x + 100
0.2(x + 100) = x
0.2x + 20 = x
20 = x - 0.2x
20 = 0.8x
x= 20/0.8
x= 25 g
What do neurons and protons have in common?
Answer:
Protons and neutrons have almost the same mass and are both located in the nucleus of the atom
Answer:
Protons and neutrons have almost the same mass and are both located in the nucleus of the atom. Protons are charged particles. Neutrons are neutral particles. ... The positive charge of the protons in the nucleus is balanced by the negative charge of the electrons.
The graph compares the kinetic energies of the molecules in four gas samples. Each graph shows a normal distribution, so the average is the center. Which sample is likely to have the lowest temperature? (1 point) A B C D
Answer:
d
Explanation:
i got it right
Gas A is likely to have the lowest temperature. Hence, option A is correct.
What are molecules?The smallest particle of a substance has all of the physical and chemical properties of that substance. Molecules are made up of one or more atoms.
In a gas, the kinetic energy is directly proportional to the temperature under constant pressure and volume.
As you can see in the problem, the average of A has low kinetic energy. But the average is increasing between B, C and D.
As gas A has the lowest average kinetic energy:
Gas A is likely to have the lowest temperature
Hence, option A is correct.
Learn more about molecules here:
https://brainly.com/question/28069497
#SPJ2
Which of the following is a halogen?
O A. Neon (Ne)
B. Iodine (1)
O C. Oxygen (0)
O D. Potassium (K)
Answer:
[tex]\boxed{\mathrm{Iodine}}[/tex]
Explanation:
Halogens are elements in group 17 or 7 in the periodic table.
Iodine is a halogen.
Therefore, iodine, an Halogen
Learn more at: https://brainly.com/question/15852546?referrer=searchResults
Which two features of Earth's crust involve tension?
O A. Convergent boundaries
B. Reverse faults
c. Divergent boundaries
O D. Normal faults
Answer:
The correct options are;
C. Divergent plate boundary
D. Normal faults
Explanation:
Tensile stress tends to pull objects part by acting axially upon the object to pull the object on a cross section perpendicular to the objects cross-section
The most common stress in convergent plate boundaries is compression stress
The most common stress in divergent plate boundaries is tensile stress
In the presence of tensile stress, normal faults results in the raising of mountains due to their enormous forces
Therefore, the features of Earth's crust involving tension are divergent plate boundary and normal faults.
Answer:c and d
Explanation:
what happens when ca no3 2 is heating it gives CaO ,NO2 and 02
Answer:
balanced equation:
2Ca(NO3)2 (aq)-----> 2CaO (s) + 4NO2 (g) + O2 (g)
So heating 2 moles of Ca(NO3)2 gives 2 moles of CaO, 4 moles of NO2 and 1 mole of O2. This is a heat decomposition reaction. It gives a white precipitate (CaO), and brown pungent gas (NO2).
Answer:
The balanced equation of the reaction is below.
Explanation:
2Ca(NO3)2 -----> 2CaO + 4NO2 + O2.
Explain how temperature and volume of a gas are related and use that to make a prediction about
how you can use this information to calculate absolute zero.
Answer:
See explanation
Explanation:
Charles law gives the relationship between volume and temperature of a gas. Charles law States that, the volume of a given mass of gas is directly proportional to its temperature at constant pressure.
Theoretically, it is assumed that when the absolute zero temperature has been achieved, the volume of any ideal gas will be found to be equal to zero. If the volume of the gas is zero, it now implies that all molecular motion will be stopped. This does not happen in real gases as all gases are found to condense to solids or liquids when this temperature is exceeded.
When volume is plotted against temperature, volume of the gas approaches zero at t = −273.15 °C, which is the x-intercept of the Charles law graph. Below this temperature, we can only get negative values of volume which does not exist hence, −273.15 °C is the lowest attainable temperature also known as the absolute zero.