Answer:
K and Mg
Explanation: This is because: Discussion of calcium is often paired with magnesium, and for good reason. As neighbors on the periodic table, they have similar chemical properties and behave similarly in several chemical reactions. They share some regulatory mechanisms and act in many of the same physiologic arenas.
1. What are the two effects of the continental plate/continental plate convergent boundary?
2. Where can you find an example of this type of divergent boundary? Which country, continent or ocean?
Answer
oh you again?
Explanation:
The half life of iodine-125 is 60 days. What fraction of iodine-125 nuclides would be left after 360 days?
Explanation:
The half-life is the time taken for a radioactive substance to decay to half of its original composition.
Let us assume that the original amount is x atoms;
Half - life = 60days
Days Composition Half-life number
0 x 0
60 x/2 1
120 x/4 2
180 x/8 3
240 x/16 4
300 x/32 5
360 x/64 6
The fraction that would be left after 360 days will be [tex]\frac{1}{64}[/tex]
How many liters are in 7.41 x 1026 atoms of helium (He) at STP?
Answer:
Explanation: Avogadro number,N, = 6.02214076*10^23per mole —> 22.71L
—>( 7.41*10^26/N)*22.71 = 22.79*10^3 = 22,790L
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Shure what you need help with
Decide whether the compound is ionic or molecular, if you can.
A Compound is a deep red solid with a noticeable unpleasant smell. It dissolves slightly in water, and a solution of in of water doesn't change the electrical conductivity of the water.
Answer:
Molecular solid
Explanation:
A molecular solid has a low melting point, they are soft and do not conduct electricity.
We have been told in the question that the solid does not really dissolve in water and it's solution does not improve the electrical conductivity of water. Hence, it must be a molecular solid.
what is the thing that you change in an experiment so that you can study the result of the change its called?
Which is a characteristic of a solution?
Its particles scatter light.
Its particles are evenly distributed.
Its particles settle out.
It has large suspended particles.
Answer:
Its particles are evenly distributed.
Explanation:
Solutions are homogenous mixtures of solutes and solvents. In a solution the solute particles are evenly distributed in the solvent.
Here are some characteristics of solutions:
The size of the particles is small The particles do not settle on standingThe particles pass through ordinary filter papersThe particles pass through permeable membranesThe particles are not visible with microscope or the naked eyes. They are clear and may have a color.A characteristic of a solution is that its particles are evenly distributed.
What are solutions?A characteristic of a solution is that its particles are evenly distributed. In a solution, the solute (substance being dissolved) is uniformly distributed and mixed with the solvent (the substance doing the dissolving) at the molecular or ionic level.
The particles of the solute become thoroughly dispersed and do not settle out over time. Solutions are generally clear and do not scatter light, unlike suspensions or colloids which may exhibit light scattering due to the presence of larger particles.
More on solutions can be found here: https://brainly.com/question/30665317
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US
What is the percent of H in
NH3?
(H = 1.008 amu, N = 14.01 amu)
[?]%
Answer:
17.6
Explanation:
Answer is explained above
During which two processes does a substance absorb energy?
Answer:
melting and vaporization
Explanation:
The average atomic mass for germanium is 72.631 amu. If germanium occurred as a mixture of the two isotopes below, what would be the percent abundance of 73Ge in the mixture?
mass of 70Ge = 69.924 amu
mass of 73Ge = 72.923 amu
Percent abundance of 73Ge in nature = ________ %
Answer:
dora needs help
Explanation:
Answer:
...........................
what is the magnification of the eye piece on the microscope?
Answer:
The magnification is 10x
Explanation:
Answer: The magnification of the eyepiece on the microscope is the lens at the top of the microscope that the user looks through. This lens most commonly magnifies a sample by 10x
Explanation: The eyepiece magnifies the primary image produced by the objective; the eye can then use the full resolution capability of the objective. The microscope produces a virtual image of the specimen at the point of the distinct vision.
How do the percent compositions for C3H6 and C4H7 compare?
A. They are the same
B. C4H8 has a higher percentage of carbon than C3H6.
C. C4H8 has a higher percentage of hydrogen than C3H6.
D. none of the above
A. They are the same
Further explanationGiven
C3H6 and C4H8
Required
The percent compositions
Solution
C₃H₆(MW = 42 g/mol)%C = 3.12/42 x 100% = 85.71%
%H = 6.1/42 x 1005 = 14.29%
C₄H₈(MW=56 g/mol)
%C = 4.12/56 x 100% = 85.71%
%H = 8.1/56 x 100%=14.29%
So they are the same, because mol ratio of C and H in both compounds is the same, 1: 2
(9) How many moles of oleum in 1780. g of oleum? - Write an equation to summarize the process.
Answer:
1. 10moles
2. Find the summarized equation below
Explanation:
Mole = mass ÷ molar mass
Molar mass of oleum (H2S2O7) = 1(2) + 32(2) + 16(7)
= 2 + 64 + 112
= 178g/mol
According to the information provided, the mass of oleum is 1780g, hence, the number of moles in it is:
Mole = 1780/178
Mole = 10moles
2. The summarized equation of the contact process is:
1) S + O2 → SO2
2) 2SO2 + O2 → 2SO3
3) SO3 + H2SO4 (conc. sulfuric acid) → H2S2O7
4) H2S2O7 + H2O → 2H2SO4 (dilute sulfuric acid)
How do I arrange greatest to least magnitude according to absolute value? What does that mean?
-2.58 x 10^6
-4.18 x 10^-2
-5.29 x 10^-5
Answer:
[tex]-2.58\times 10^6[/tex]
[tex]-4.18\times 10^{-2}[/tex]
[tex]-5.29\times 10^{-5}[/tex]
Explanation:
The absolute value of a number is the value of the number without the sign. So, the absolute value of [tex]-1[/tex] is [tex]1[/tex] and [tex]1[/tex] is also [tex]1[/tex].
It is generally denoted in the following way [tex]|-1|=1[/tex]
Here the numbers are
[tex]|-2.58\times 10^6|=|-2580000|=2580000[/tex]
[tex]|-4.18\times 10^{-2}|=|-0.0418|=0.0418[/tex]
[tex]|-5.29\times 10^{-5}|=|-0.0000529|=0.0000529[/tex]
So, the order of the numbers from greatest to the least is
[tex]-2.58\times 10^6[/tex]
[tex]-4.18\times 10^{-2}[/tex]
[tex]-5.29\times 10^{-5}[/tex]
How many electrons does a single hydrogen gain or lose in the following reaction?
H2 + O2 - H20
Answer:
One electron per single hydrogen atom.
Explanation:
Hello!
In this case, given the reaction:
[tex]H_2+O_2\rightarrow H_2O[/tex]
Whereas we can identify the following half-reaction for hydrogen:
[tex]H_2^0\rightarrow H_2^+[/tex]
Whereas we see that each single hydrogen atom gains one electron in order to go from 0 to +1, which is also related to an oxidation half-reaction.
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The number of moles left = 0.0067 moles
Further explanationGiven
0.28 g CO
2 x 10²¹ molecules removed
Required
Number of moles left
Solution
Initial mol of CO(MW=28 g/mol) :
mol = 0.28 : 28
mol = 0.01
The number of molecules in 0.01 mol :
= 0.01 x 6.02 x 10²³
= 6.02 x 10²¹
2 x 10²¹ molecules removed, so molecules left :
= 6.02 x 10²¹ - 2 x 10²¹
= 4.02 x 10²¹
moles of 4.02 x 10²¹ :
= 4.02 x 10²¹ : 6.02 x 10²³
= 0.0067 moles
Imagine an alternate universe where the value of the Planck constant is 6.6207 x 10^-36 J*s.
In that universe, which of the following objects would require quantum mechanics to describe, that is, would show both particle and wave properties? Which objects would act like everyday objects, and be adequately described by classical mechanics?
1. A buckyball with a mass of 1.2 x 10-21 g, 0.7 nm wide, moving at 38. m/s.
classical or quantum?
Answer:
See explanation
Explanation:
According to Louis de Broglie, matter has an associated wavelength. He was the first scientist to establish the idea of wave-particle duality or wave- particle paradox.
The display of wavelike properties by objects in the universe is dependent on the magnitude of the of the mass of the body. Small objects have a large associated wavelength and can be described completely by quantum mechanics.
A buckyball with a mass of 1.2 x 10-21 g, 0.7 nm wide, moving at 38. m/s has a very small mass and significant associated wavelength hence the system can be completely described by quantum mechanics.
You want to determine the concentration of a phosphoric acid (H3PO4) solution using a standardized 0.0995 M NaOH solution. 10.00 mL of the H3PO4 solution needed to be titrated with 22.85 mL of the standardized 0.0995M NaOH solution to reach the equivalence point. What is the concentration of the H3PO4 solution
Answer:
Explanation:
H₃PO₄ + 3NaOH = Na₃PO₄ + 3 H₂O.
1 mole 3 mole
22.85 mL of the standardized 0.0995M NaOH solution will contain
.0995 x .02285 moles of NaOH
= 22.7357 x 10⁻⁴ moles of NaOH
3 moles of NaOH reacts with 1 mole of H₃PO₄
22.7357 x 10⁻⁴ moles of NaOH reacts with 1 x 22.7357 x 10⁻⁴ / 3 mole of H₃PO₄
= 7.5785 x 10⁻⁴ moles of H₃PO₄
7.5785 x 10⁻⁴ moles of H₃PO₄ is contained in 10 mL or 10⁻² L
molarity of H₃PO₄ solution = 7.5785 x 10⁻⁴ / 10⁻²
= 7.58 x 10⁻² M
= .0758 M .
What is the amplitude of a wave?
Answer:
the total distance moved by the wave from it's equilibrium point.
Explanation:
I picture the equivalent as standing on the floor is equilibrium point or starting. how high you jump is your amplitude.
While in Europe, if you drive 123 km day, much you spend on gas in one week it gas costs 1.10 euros per liter and your car's gas mileage is 27.0mi / g * a * l ? Assume that 1 euro = 1.26 dollars.
Money spend = $103.86
Further explanationGiven
Distance :123 km/day
cost 1.1 euros/L
your car's gas mileage is 27.0mi / gal
Required
Money needed
Solution
Distance/week : 123 x 7 = 861 km/week
1 km = 0.621 miles, so for 861 km =
861 x 0.621 = 534.68 miles/week
Amount of gas : 534.68 miles : 27 miles/gal = 19.8 gal
1 gal = 3.785 L , so 19.8 gal =
19.8 x 3.785 = 74.94 L
Cost for euros = 74.94 x 1.1 = 82.43
Cost for dollars = 82.43 x 1.26 = $103.86
What is Sr(NO3)2 + ZN ?
Answer:
strontium nitrate
Explanation:
hope this helps you....:)
Sodium chloride (NaCl) is an ionic compound. We can effectively model it as sodium atoms with one electron removed next to chlorine atoms with one electron added. The attractive force between the positive and negative charges holds the crystal together. If we model the sodium and chlorine ions as point charges separated by 0.28 nm, the spacing in the crystal, what is the magnitude of the attractive force between two adjacent ions
Answer:
The attractive force between the sodium and chloride ions has a magnitude of -2.94 x 10⁻⁹ N
Explanation:
An electron is a negatively-charged particle. The charge on an electron is -1.6 x 10⁻¹⁹ C. This is also known as the fundamental unit of charge, e. A proton has the same charge as as electron but its charge is positive.
The charge on the chloride ion is negative and is due to an electron whereas the charge on the sodium ion is positive and is due to a proton.
The magnitude of the force of attraction between two charges is given by the Coulomb's law: F = Kq₁q₂/r²
where K is a constant = 9 x 10⁹ N.m₂.C⁻², q₁ = -1.6 x 10⁻¹⁹ C, q₂ = +1.6 x 10⁻¹⁹ C, r = 0.28 nm = 0.28 x 10⁻⁹ m
F = {(9 x 10⁹ N.m₂.C⁻²) (-1.6 x 10⁻¹⁹ C) (+1.6 x 10⁻¹⁹ C)} / (0.28 x 10⁻⁹ m)²
F = -2.94 x 10⁻⁹ N
Therefore, the attractive force between the sodium and chloride ions has a magnitude of -2.94 x 10⁻⁹ N
Read the descriptions below of two substances and an experiment on each. Decide whether the result of the experiment tells you the substance is a pure substance or a mixture, if you can .
Sample A is 100.mL of a clear liquid. The density of the liquid is measured, and turns out to be 0.77/gmL. The liquid is then heated in a flask until it boils. The vapor that rises off the boiling liquid is collected for 10 minutes and cooled until it condenses into a separate beaker. The density of the liquid that remains in the flask is then measured, and turns out to be 1.04/gmL.
Sample B is 100.g of a coarse grey powder with a faint unpleasant smell. 15.g of the powder are dissolved in ethanol. 0.5mg of the resulting black solution is carefully dropped onto a thick sheet of paper laid flat in a tray. After 30 minutes the initial round black stain has spread out and faded in color to a deep purple. Additionally, there is a dark green ring surrounding the inner stain.
a. Is sample A made from a pure substance or a mixture?
b. If the description of the substance and the outcome of the experiment isn't enough to decide, choose "can't decide.
c. Is sample B made from a pure substance or a mixture?
d. If the description Of the substance and the outcome of the experiment isn't enough to decide, Choose "can't decide.
Answer:
Samples A and B are mixtures
Explanation:
For sample A, we were told that the initial density of the solution is 0.77/gmL. After distillation, the liquid left has a density of 1.04/gmL. Apparently, A is a mixture of liquids.
As for sample B, the spread of the chromatogram resulting in different colours show that the sample B is not pure. It is a mixture of substances. A pure sample will yield only a single spot.
50 POINTS PLUS BRAINLIEST NEED HELP ASAP
Please solve these 5 questions
Answer:
Argon 7.89693x10^25 atoms
Gold 4.1949252x10^25 atoms
Carbon Monoxide 34.55149 moles
Potassium oxide 1.6 moles
Calcium 4.4969x10^24 atoms
Explanation:
Its done with dimensional analysis i can not put the full work here because it would look to sloppy
according to the bohr model of an atom, what happens when an electron moves from the second energy level to the third energy level and then back to the second energy level?
Answer:
when the atom moves to the third energy level, its energy increases. However, when it goes back to the second energy level its overall energy decreases.
Explanation:
the smallest (or innermost) energy level has the least amount of energy and the largest (or outer most) level needs the most amount of energy. In order for the electron to move from one level to the other, it would need to match the energy of that level.
matter can undergo chemical reactions and nuclear reactions. which properly is conserved in nuclear reactions?
Answer:change in number of atoms
Explanation:AP3X
Which macromolecules break apart by hydrolysis?
Answer:
Dehydration synthesis reactions build molecules up and generally require energy, while hydrolysis reactions break molecules down and generally release energy. Carbohydrates, proteins, and nucleic acids are built up and broken down via these types of reactions, although the monomers involved are different in each case.
Explanation:
What is the mass number of an atom containing 4 protons and 5 neutrons
Is Gold (Au) soluble?
Answer:
yes
Explanation:
Twelve grams of gas occupies 14.5 liters at a pressure of 52.0cm Hg. What is the volume when the pressure has increased to 85.0cm Hg?
Answer:
8.87 L.
Explanation:
From the question given above, the following data were obtained:
Mass (m) of gas = 12 g
Initial volume (V₁) = 14.5 L
Initial pressure (P₁) = 52 cmHg
Final pressure (P₂) = 85 cmHg
Final volume (V₂) =?
The final volume of the gas can be obtained by using the Boyle's Las equation as illustrated below:
P₁V₁ = P₂V₂
52 × 14.5 = 85 × V₂
754 = 85 × V₂
Divide both side by 85
V₂ = 754 / 85
V₂ = 8.87 L
Thus the volume of the gas will be 8.87 L