Answer:
D
Explanation:
In the Rb atom the valence electron is farther from its nucleus than the valence electron of Li is from its nucleus
Find the molarity of 4.18 g MgCI2 in 500mL of water
Answer:
The molarity of MgCl₂ in water is 0.088 mol/L.
Explanation:
The molarity of MgCl₂ can be calculated as follows:
[tex] C = \frac{\eta}{V} = \frac{m}{MV} [/tex]
Where:
C: is the molarity =?
η: is the number of moles of MgCl₂ = m/M
V: is the volume of water = 500 mL = 0.500 L
m: is the mass of MgCl₂ = 4.18 g
M: is the molar mass of MgCl₂ = 95.211 g/mol
Hence, the molarity is:
[tex] C = \frac{m}{MV} = \frac{4.18 g}{95.211 g/mol*0.500 L} = 0.088 mol/L [/tex]
Therefore, the molarity of MgCl₂ in water is 0.088 mol/L.
I hope it helps you!
Calculate the pOH for a solution with a pH of 12.34. Is the Solution acidic or basic?
Answer:
1.66 basic
Explanation:
How many formula units are in 325 grams of iron (III) chloride?
Answer:
1.204 × 10^24 formula units
Explanation:
Using the following formula to convert mass of iron (III) chloride to moles;
mole = mass/molar mass
Molar mass of FeCl3 = 56 + 35.5(3)
= 56 + 106.5
= 162.5g/mol
Mole = 325/162.5
mole = 2mol
Next, to calculate the formula units of FeCl3, we multiply the number of moles of FeCl3 by Avagadro number (6.02 × 10^23)
Formula units of FeCl3 = 2 × 6.02 × 10^23
12.04 × 10^23
= 1.204 × 10^24 formula units.
5) How many Kilograms are in 12 L of Chlorine Gas?
Answer: 0.03798 kilograms
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given volume}}{\text {Molar Volume}}=\frac{12L}{22.4L}=0.535moles[/tex]
1 mole of chlorine gas [tex](Cl_2)[/tex] weighs = 71 g
Thus 0.535 moles of chlorine gas [tex](Cl_2)[/tex] will weigh = [tex]\frac{71}{1}\times 0.535=37.98g=0.03798kg[/tex] (1kg=1000g)
Thus there are 0.03798 kilograms in 12 L of chlorine gas.
What could be an electron configuration of Na in the excited state?
Answer:
The excited state electron configuration shows when an electron is excited and jumps into a higher orbital. For example, sodium in its excited state would have an electron configuration of 1s2 2s2 2p6 3p1, compared with its ground state of 1s2 2s2 2p6 3s1.
Explanation:
Given the [H+] = 3.89x10^-7M, what is the pOH?
Answer:
7.59
Explanation:
How much heat, in kilojoules, is needed to raise the temperature of 236 g of silver from 8.5oC to 34.9 °C? (cAg = 0.24 J/g°C)
Answer:
1.49kJ
Explanation:
Using the formula as follows;
Q = m × c × ∆T
Where;
Q = amount of heat (joules)
m = mass (g)
c = specific heat of silver (J/g°C)
∆T = change in temperature (°C)
According to the information given in this question;
mass of Silver (Ag) = 236g
c of Ag = 0.24 J/g°C
initial temperature (T1) = 8.5°C
final temperature (T2) = 34.9°C
∆T = T2 - T1 = 34.9 - 8.5 = 26.4°C
Using Q = m × c × ∆T
Q = 236 × 0.24 × 26.4
Q = 1,495.3 Joules
Amount of heat needed to raise the temperature of Silver (Q) in kilojoules is 1495.3/1000 = 1.4953
Q = 1.49kJ
Which best describes the role of the nephrons ?
Nephrons collect salts to be stored for later use by the body.
Nephrons signal the bladder to release excess urine.
O Nephrons transport urine to the bladder.
Nephrons restore the substances and water the body needs.
Answer:
c
Explanation:
edge 2021
Answer:
c
Explanation:
PLS HELP ASAP NO LINKS
What type of scientist studies matter and its composition?
Biologist
Chemist
Physicist
Engineer
Answer:
.biology and maybe physics
Answer:
Biologist
ExplanationBiologist Unlike the above type of scientist, geoscientists’ work involves exploring the earth and its internal environment. They study the composition, structure, and processes of the earth by being indoors and outdoors. They contribute to the discovery of mines, petroleum deposits, minerals, and other aspects of the earth.
2. Explain how an ionic bond is formed. Use the words "metal", "transfer", "nonmetal”, “cation", "anion" and
"attraction" in your description
Forming an Ion Ionic bonds are a class of chemical bonds that result from the exchange of one or more valence electrons from one atom, typically a metal, to another, typically a nonmetal. This electron exchange results in an electrostatic attraction between the two atoms called an ionic bond.
Select the correct image.
The image shows the embryonic development of four different types of vertebrates. Which developmental path is most likely that of a lizard?
Answer:
what image?????
Explanation:
?
Answer:
2nd image/ image B
Convert 6.71 moles NH3 to number of molecules.
Answer: There are [tex]40.41 \times 10^{23}[/tex] molecules present in 6.71 moles of [tex]NH_{3}[/tex].
Explanation:
Given: Moles of [tex]NH_{3}[/tex] = 6.71 mol
According to the mole concept, 1 mole of every substance contains [tex]6.022 \times 10^{22}[/tex] molecules.
Therefore, molecules present in 6.71 moles are calculated as follows.
[tex]Molecules = moles \times 6.022 \times 10^{23}\\= 6.71 \times 6.022 \times 10^{23}\\= 40.41 \times 10^{23}[/tex]
Thus, we can conclude that there are [tex]40.41 \times 10^{23}[/tex] molecules present in 6.71 moles of [tex]NH_{3}[/tex].
What is the OH- ion concentration, in moles per liter, of an aqueous solution with a pH of 7?
A. 1 × 10-14
B. 1 × 10-7
C. 7
D. 14
Answer:
B
Explanation:
the pH scale is based on the function
1x10-14
So since pH is neutral the concentration of OH and H must be equal hence the only option in which the concetration would [OH]{H}= 1x10-14 would be when both are equal so it cannot be a or d and when they are expressed in concetration so the only option is B.
The pH of the solution can be used to give the relation between the pOH and the hydroxide ion concentration. The concentration of hydroxide ions is 1 ×10⁻⁷. Thus, option B is correct.
What is pOH?pOH is the measure of the hydroxide ion in the solution. The hydroxide concentration from pH is related as:
pH = - log [H⁺]
[H⁺] = 10⁻⁷
= 1 × 10⁻⁷
The hydroxide concentration from hydrogen concentration is calculated as:
[H⁺][OH⁻] = 1 × 10⁻¹⁴
[OH⁻] = (1 × 10⁻¹⁴) ÷ (1 × 10⁻⁷)
= 1 ×10⁻⁷
Therefore, option B. 1 ×10⁻⁷ is the hydroxide ion concentration.
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En una muestra de jugo de limón la concentración de H1 es de 3.8x10 a la 4 potencia ¿ cual es su PH considerando que 378= 0.58
Answer:
pH = 3.42
Explanation:
Para calcular el pH necesitamos usar la siguiente expresión:
pH = -log[H⁺]
Por tanto, solo necesitamos reemplazar el valor dado de [H⁺] en la expresión anterior y se determina su pH:
pH = -log(3.8x10⁻⁴)
pH = 3.42Por tanto el pH de la muestra de jugo de limón es 3.42
Two glass rods are rubbed together. One of the glass rods are brought near (but
does not touch) an uncharged pith ball. Would you expect the pith ball to attract,
repel, or do nothing? Explain why.
Answer:
Do Nothing
Explanation:
Charges are transferred by friction when two different types of bodies are rubbed together. This is known as charging by friction.
However, when two materials of the same type are rubbed together, no charge is transferred from one object to the other hence there is no transfer of charges by friction and none of the two glass rods are charged.
Therefore, when one of the glass rods is brought close but does not touch the pith ball, nothing happens.
need these 2 answered asap pls
Answer:
im not a brain wiz but i think 20
Explanation:
PLZ HELP!!!!!! IN YOUR OWN WORDS PLZ! :D
Imagine your cell phone rings. Describe how the sound gets transmitted from your phone to your ear, and then, from your ear to your brain. In your response, be sure to mention the type of wave that a sound wave is, the medium the sound is transmitted through before it gets to your ear, and what happens in your ear once the sound reaches it.
Answer:
SOUND WAVE (carried by thin metal inside the phone) ⇒ELECTRICAL ENERGY (over the wire) ⇒SOUND WAVE (that is heard by someone on the side of the phone)
Explanation:
What is a sound wave?A wave that is comprised of compression and refraction, by which sound is propagated in an elastic medium such as air.
How does sound get transmitted from phone to ear?
The sound waves are carried to a thin metal disk inside the phone, known as the diaphragm, and are converted into electrical energy. The electrical energy travels over wires to another phone and is converted from electrical energy to sound waves again which can be heard by the one on the other end of the phone.
How does sound get transmitted from ear to brain and what happens when sound reaches the ear?Sound waves enter the outer ear and travel through a small passageway (ear canal), which leads to the eardrum.The eardrum vibrates from the coming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are known as the malleus, incus, and stapes.The bones present in the middle ear amplify the sound vibrations and send these vibrations to the cochlea (the snail-shaped structure that is filled with fluid present in the inner ear). An elastic separation runs from the beginning to the edge of the cochlea, splitting it into upper and lower parts. This separation is called the basilar membrane as it serves as the base on which key hearing structures sit.Once the vibrations result in the fluid inside the cochlea rippling, a traveling wave appears along the basilar membrane. Hair cells (sensory cells) sitting on top of the basilar membrane ride the wave. Hair cells near the broad end of the cochlea detect higher-pitched sounds. Those closer to the center detect lower-pitched sounds, such as a large dog barking.As the hair cells move up and down, microscopic hair-like projections (known as stereocilia) that perch on the peak of the hair cells crash against an overlying structure and bend down. Bending results in pore-like channels, which are at the tips of the stereocilia, opening up. Then chemicals rush into the cells, producing an electrical signal.The auditory nerve carries this electrical signal to the brain, which in return it into a sound that we recognize and understand.In this way, sound reaches our ears.
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The first organisms to arrive in an ecosystem?
What is the molarity of 40ml of NaOH if it takes 25ml of 0.5 molar HCl to neutralize it?
Answer:
Molarity of 40 ml of NaoH is 0.3125 mL
Explanation:
As we know
Molarity of acid * volume of acid = molarity of base * volume of base
Substituting the given values, we get
[tex]0.5 * 25 = X* 40 \\X = \frac{0.5*25}{40} \\X = 0.3125[/tex]
Molarity of 40 ml of NaoH is 0.3125 mL
Select the correct answer.
A circuit is used in which process?
OA. electricity
OB. magnetism
OC. velocity
OD. gravity
Answer:
electricity
Explanation:
A circuit is used in every electrical and electronics operation.
The enthalpy of a reaction is -1207 kJ/mol. Which of the following best
describes this reaction?
Answer:
D. Exothermic
Explanation:
The enthalpy, ΔH, of a reaction is defined as the change in heat when a reaction occurs.
A reaction with ΔH > 0 is called endothermic and requires energy to be produced
A reaction with ΔH < 0 is called exothermic and produce energy when occurs (An example is the combustion of octane that produce energy that is used in engines to produce movement)
As the enthalpy of the reaction is -1207kJ/mol (ΔH < 0) the reaction is:
D. Exothermic2 P + 5 Cl2=2 PCl3 +886.0 kJ
How much energy will be produced when 1.382 mol P reacts with excess
Cl2?
Answer:
612.2kJ are produced
Explanation:
Based on the reaction:
2P + 5Cl₂ → 2PCl₃ + 886.0kJ
When 2 moles of P react with an excess of chlorine 886.0kJ are produced (That is 886.0kJ / 2mol P).
To solve this question we must use the last statement as follows:
1.382mol P * (886.0kJ / 2mol P) =
612.2kJ are producedBeryllium hydrogen carbonate is more than 3% hydrogen by mass.
True
False
The balanced equation below represents a reaction between propane and oxygen. C3H8 + 5 O2 → 3 CO2 + 4 H2O According to this equation, which ratio of propane to oxygen is correct? 5 grams CO2 1 gram C3H8 3 moles CO2 1 mole C3H8 5 moles O2 1 mole C3H8 3 moles CO2 4 moles H2O
Answer:
5 moles O2 1 mole C3H8
Explanation:
In the question, it is mentioned about the ratio Propane and Oxygen. So the the ration will be 1:5 i.e, 5 moles of O2 1 mole C3H8. There is only one option which mentions both Propane and Oxygen and others doesn't.
What is important in order for a radioisotope to provide accurate dating
results?
O A. The half-life should be similar to the age of the object.
B. The radioisotope cannot be part of a decay chain.
O C. The isotope must undergo transmutation.
O D. The item being dated must be very old.
The most important factor to be considered in order for a radioisotope to provide accurate dating simply is:
The half-life should be similar to the age of the object.
The correct answer choice is option a.
Why half-life should be similar to the age of the object in determining accurate dating of a radioisotope.Half-life of radioisotope helps in determining dating accurately simply because it helps to predict the amount of radioactive substance remaining after a given period of time.
In conclusion, it can be perfectly deduced from the explanation given above that the half-life of a radioisotope usually, frequently and most of the time helps to determine the rate at which these substances decay.
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If you stay at 90 degrees Celsius and a gas in a liquid solution has a pressure of 2 atm, what solubility should it have if it has a solubility of 64 g/L at a pressure of 8 atm?
Answer:
im not sure
Explanation:
Which product is made from nonmetallic mineral resources?
a. Stainless steel
b. iron nails
c. Copper wires
d. concrete
Answer:
Concrete
Explanation:
What type of wave has the SHORTEST wavelength and the highest frequency?
Answer:
The answer is gamma rays.
Explanation:
Gamma rays have the highest energies, the shortest wavelengths, and the highest frequencies on the electromagnetic spectrum.
what will litmus paper turn when it reacts with sodium nitrate?
WILL MARK BRAINLEISTTTT
HELPPPPPP
Substitute symbols and formulas for names and write balanced equations for each of the
reactions described below.
a) When copper(II) carbonate is heated, it forms copper(II) oxide and carbon dioxide gas.
b) Ammonium nitrate decomposes to water and dinitrogen monoxide.
c) Barium hydroxide reacts with carbon dioxide to form barium carbonate and water.
d) Sodium reacts with water to produce sodium hydroxide and hydrogen gas.
Answer:
jkrifhcuhixjck
gvudd
Explanation:
dugucdsorfooggigj
a CUCO3(s) + ( I don't have the symbol on my phone ) delta CUo(s) + CO2(g)
b NH4NO3➡️ HNo3 + H2O
c. Ba(OH)2+CO2 ➡️ BaCO3+H20
d Na +H20 ➡️NaOH +h2
Explanation:
I think this should be it , I think that 8s the symbol for hydrogen gas if its not correct I'm sorry