(b) Potassium and sodium are kept in dark reagent bottles filled with paraffin oil.
Explain why.
Answer:
these metals are stored in kerosene because kerosene contains no water and protects these metals from being exposed to any moisture in the air that would cause these metals to react, potentially violently.
The pH of a solution with a Hydronium (H30+) ion concentration of 0.001M is
Answer:
The pH of a solution with a Hydronium (H₃O⁺) ion concentration of 0.001 M is 3.
Explanation:
pH, short for Hydrogen Potential, is a measure used to establish the level of acidity or alkalinity of a solution.
pH indicates the amount of hydrogen ions present in a solution or substance. Mathematically the pH is the negative logarithm of the molar concentration of hydrogen ions or protons (H⁺) or hydronium ions (H₃O⁺).
pH= - log [H⁺]= - log [H₃O⁺]
The pH scale goes from 0 to 14. Values less than 7 indicate the range of acidity and those greater than 7 indicate alkalinity or basicity. The value 7 is considered neutral.
In this case, [H₃O⁺]= 0.001 M.
Replacing in the definition of pH:
pH= - log (0.001 M)
Solving:
pH= 3
The pH of a solution with a Hydronium (H₃O⁺) ion concentration of 0.001 M is 3.
The geometry of a ______________ makes it a very stable shape.
Answer:
triangles
Explanation:
A solution of KOH is prepared with a [OH-] concentration of 3.3 × 10-2 M. Calculate [H+], pH, and identify whether the solution is acidic, basic, or neutral.
Answer:
[H⁺] = 3.03x10⁻¹³ MpH = 12.52The solution is basicExplanation:
We can first calculate [H⁺] by using the formula:
[H⁺] * [OH⁻] = 1x10⁻¹⁴[H⁺] * 3.3x10⁻² = 1x10⁻¹⁴[H⁺] = 3.03x10⁻¹³ MNow we proceed to calculate pH:
pH = -log [H⁺]pH = -log (3.03x10⁻¹³)pH = 12.52As the pH is higher than 7, the solution is basic.
How much energy is required to raise the temperature of 74 g of water from 19 °C to 47 °C.
Answer:
The energy required is 8660.96 J.
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
Sensible heat is the amount of heat that a body absorbs or releases without any changes in its physical state (phase change). This heat is given by the expression:
Q = c * m * ΔT
where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case, you know:
C= 4.18 [tex]\frac{J}{g*C}[/tex]m= 74 gΔT= Tfinal - Tinitial= 47 C - 19 C= 28 CReplacing:
Q= 4.18 [tex]\frac{J}{g*C}[/tex] *74 g* 28 C
Solving:
Q= 8660.96 J
The energy required is 8660.96 J.
The diagram below represents the bone
arrangements in the front limbs of three different
species of mammals.
The similarities and differences in these limbs
suggest that all three species developed from the
same ancestor, but
Answer:
these species share a common ancestor
Explanation:
¿A que se refiere la amplitud de una onda sinusoidal?
the answers that can be written down are at the bottom
Answer:
increasing / protons / periods / groups / center / far right / similar
What is the velocity of a wave with a wavelength of 0.03 m and a frequency of
120 Hz?
A. 0.28 m/s
B. 4000 m/s
C. 3.6 m/s
D. 2.5x 10-4 m/s
Answer:
A
Explanation:
Got a calculation of 8.05297
Answer:
C. 3.6 m/s
Explanation:
I just took a test on a-pe-x and it was correct! :)
calculate the molar mass for BaSO4
Answer:
233.38 g/mol
Explanation:
you find the molar mass of each element and then add them up.
i need help with this pls
I know it’s E and A
Explanation: did you count it’s exactly 28, also the electrons are not visible.
Ps: I’m in 5th grade, what grade is this, if my suggestion was correct then holy crackers.
Why does the chloride ion have a charge of -1
Explanation:
As we know that chloride ion is halogen. So it has seven valence electrons in its valence shell. Hence it gains one electron from others during chemical reaction to be stable. So Chloride ion have a negative charge of -1.
Hope it will help :)❤
PLEASE HELP HELP ME. THIS IS DUE TODAY PLEASE
Answer:
C
Explanation:
cause i'm smart
Answer:
D
Explanation:
Because it says tree roots breaking rocks into smaller rocks.
Hope this helped!
What keeps mountains from being even taller than they
already are?
Answer:
Three main processes control mountain height: lateral support of mountains from tectonic forces, which stops mountains from collapsing under their own weight or pushes them up against gravity; climate-controlled erosion; and isostasy, which keeps mountains afloat on the hot and soft mantle material.
Explanation:
List three strategies for answering questions that you don't know anything
about?
Help please I'll give brainless no links, please I've been asking this question from this morning, and no one answer
A greater force is required to move an object with a larger mass than one with a smaller
mass.
Answer:
Explanation:
what do u need to know
What causes the pressure inside oxygen tanks to change as they are filled?
A. The temperature of the gas changes.
B. The volume of the container changes.
C. The pressure outside the tanks changes.
D. The number of gas molecules changes.
Answer:
The answer would be D.
: )
Explanation:
The number of gas molecules changes as the pressure inside oxygen tanks changes as they are filled. option D is correct.
What are oxygen tanks?Oxygen tanks are those in which the oxygen is filled in the liquid form by giving pressure to it with the help of a piston due to more pressure the molecules of oxygen become close.
As the molecule of the oxygen gas is closed to each other they are condensed and changes their state from a gaseous state to a liquid state.
By providing more pressure to the oxygen tank the gas molecules increases due to the decrease in the surface of the tank and molecules condense to liquid form.
Therefore, The number of gas molecules changes as the pressure inside oxygen tanks changes as they are filled. option D is correct.
Learn more about oxygen tanks, here :
https://brainly.com/question/825076
#SPJ2
Help please I’m confused
Answer:1 answer number 1
Explanation:
YALL KNOW WHATS UPPPPP
HAIIIII REEEEEEE
answer this question no links
Answer:
it is b, a stethiscope is the thing they put on your heart
Explanation:
2. A sample of helium gas has a volume of 200.0 mL at 0.960 atm. What pressure, in atmospheres, is needed to reduce the volume at constant tem-perature to 50.0 mL?
Answer:
3.840 atm
Explanation:
We use Boyle's law, which relates the pressure (P) and the volume (V) of a gas at a constant temperature. The change from initial P and V (P₁ and V₁) to final P and V (P₂ and V₂) is expressed as:
P₁V₁ = P₂V₂
We have the following data:
P₁= 0.960 atm
V₁= 200.0 mL
V₂ = 50.0 mL
Thus, we introduce the data in the equation and calculate the final pressure P₂:
P₂ = P₁V₁/V₂= (0.960 atm x 200.0 mL)/50.0 mL = 3.840 atm
Therefore, a pressure of 3.840 atm is needed to reduce the volume of the gas from 200.0 mL to 50.0 mL.
You mix two amino acids together: glu and ser. If they reacted, how many different dipeptides would you expect to get? List them.
I'm really struggling with amino acids, so any help is appreciated! I won't be clicking any links, though.
Answer:
Answers 1. An amide linkage between the carboxyl group of one amino acid and the amine group of the other amino acid. 2. An ester is a compound formed from the reaction of a carboxylic acid and an alcohol. ( I apologise, I cant figure out number 3.. )
What is the ph of H2?
Answer:
Hydrogen ion concentration is more conveniently expressed as pH, which is the logarithm of the reciprocal of the hydrogen ion concentration in gram moles per liter. Thus, in a neutral solution the hydrogen ion (H+) and the hydroxyl ion (OH−) concentrations are equal, and each is equal to 10−7. A pH of 7 is neutral
What is the wavelength of a photon with a frequency of 7.81 x 1014 Hz?
Explanation:
If you know the frequency of the photon, you can calculate the wavelength using the equation λ=cν where c is the speed of light and ν is the frequency.
λ=cν
f=T^-1,f=1/7.81×1014s
c=3×10^8m/s
λ=3×10^8m/s×1/7.81.×1014s
λ=37881.94m
The difference between a conjugate acid/base pair is
+
o the conjugate acid
o the conjugate base
O one proton
one OH-
Answer:
hola no ablo inglés porfavor
Explain why using standard chemical names for compounds would be important when working in a laboratory.
Answer:
░░ ░░░░▄░░░░░░░░░ ▄ ░░░░░░░░▌▒█░░░░░░░░░░░▄▀▒▌ ░░░░░░░░▌▒▒█░░░░░░░░▄▀▒▒▒▐ ░░░░░░░▐▄▀▒▒▀▀▀▀▄▄▄▀▒▒▒▒▒▐ ░░░░░▄▄▀▒░▒▒▒▒▒▒▒▒▒█▒▒▄█▒▐ ░░░▄▀▒▒▒░░░▒▒▒░░░▒▒▒▀██▀▒▌ ░░▐▒▒▒▄▄▒▒▒▒░░░▒▒▒▒▒▒▒▀▄▒▒▌ ░░▌░░▌█▀▒▒▒▒▒▄▀█▄▒▒▒▒▒▒▒█▒▐ ░▐░░░▒▒▒▒▒▒▒▒▌██▀▒▒░░░▒▒▒▀▄▌ ░▌░▒▄██▄▒▒▒▒▒▒▒▒▒░░░░░░▒▒▒▒▌ ▌▒▀▐▄█▄█▌▄░▀▒▒░░░░░░░░░░▒▒▒▐ ▐▒▒▐▀▐▀▒░▄▄▒▄▒▒▒▒▒▒░▒░▒░▒▒▒▒▌ ▐▒▒▒▀▀▄▄▒▒▒▄▒▒▒▒▒▒▒▒░▒░▒░▒▒▐ ░▌▒▒▒▒▒▒▀▀▀▒▒▒▒▒▒░▒░▒░▒░▒▒▒▌ ░▐▒▒▒▒▒▒▒▒▒▒▒▒
Explanation:
PS.
13. Calculate the number of representative particles of each substance.
a. 11.5 mol Ag
c. 0.150 mol NaCl
b. 18.0 mol H2O
d. 1.35 x 10-2 mol CH4
A compound has an empirical formula of CH20. What is its molecular formula, if its molar mass is 360 g/mol?
a. C6H12O6
b. C12H24O12
Answer:
a
Explanation:
A actual molecule of glucose contains six carbon atoms, twelve hydrogen atoms, and six oxygen atoms.
Answer:
B.
Explanation:
Sample A has a mass of 40g and a volume of 10cm^3. Sample B has a volume of 15cm^3 and a mass of 45g. Which sample has a greater density? Show your work.
The Answer Is Sample A
Density -
[tex]density = \frac{mass}{volume} [/tex]
Input The Formula For Both Equations To Find Density.
Sample A -
[tex]d = \frac{40}{10} [/tex]
[tex]d = 4[/tex]
Sample B -
[tex]d = \frac{45}{15} [/tex]
[tex]d = 3[/tex]
A chemist mixed two substances together: a colorless liquid with a strong smell and a white solid with no smell. The substances’ repeating groups of atoms are shown above on the left. After they were mixed, the chemist analyzed the results and found two substances. One ending substance had the repeating group of atoms shown above on the right.
Is the ending substance the same substance as the colorless liquid? What happened to the atoms of the starting substances when the ending substances formed? Be sure to explain your answers to both of these questions.
Answer:
colorless liquid with a strong smell and a white solid with no smell. The substances’ repeating groups of atoms are shown above on the left. After they were mixed, the chemist analyzed the results and found two substances. One ending substance had the repeating group of atoms shown above on the right.
Explanation:
Determine the number of representative particles in each of the following:
(a) 0.294 mol silver
____ atoms
(b) 8.98 10-3 mol sodium chloride
____ formula units
(c) 23.3 mol carbon dioxide
____ molecules
(d) 0.310 mol nitrogen (N2)
____ molecules
Answer:
(a) 0.294 mol silver = [tex]1.770 * 10^{23}[/tex]
(b) 8.98 * 10-3 mol sodium chloride - [tex]5.407 *10^{23}[/tex]
(c) 23.3 mol carbon dioxide = [tex]1.403 * 10^{25}[/tex]
(d) 0.310 mol nitrogen (N2) = [tex]1.866 * 10^{23}[/tex]
Explanation:
In one mole there are [tex]6.022 * 10^{23}[/tex] atoms/molecules
(a) 0.294 mol silver = [tex]6.022 * 10^{23} * 0.294 = 1.770 * 10^{23}[/tex]
(b) 8.98 * 10-3 mol sodium chloride - [tex]5.407 *10^{23}[/tex]
(c) 23.3 mol carbon dioxide = [tex]23.3 * 6.022 * 10^{23} = 1.403 * 10^{25}[/tex]
(d) 0.310 mol nitrogen (N2) = [tex]0.310 * 6.022 * 10^{23} = 1.866 * 10^{23}[/tex]