Answer:
B. The cells.
call
Cells are considered the basic units of life in part because they come in discrete and easily recognizable packages. That's because all cells are surrounded by a structure called the cell membrane — which, much like the walls of a house, serves as a clear boundary between the cell's internal and external environments.
A student mixes 36.0 grams of silver nitrate solution with 30.0 grams of sodium chromate solution. The mass of the products, which includes the resulting solution and precipitate, is equal to 66.0 grams. Which of the following best explains these results
Answer:
Explanation:
The law of multiple proportions.
Which of these actions increases enthalpy in the air molecules of the Earth's
atmosphere?
A. The air being heated by the sun
B. Trees being planted in the rain forests
C. Carbon dioxide being taken in by plants during photosynthesis
D. People breathing in oxygen
HELP PLS
Answer:
The air being heated by the sun
Explanation:
Just took the quiz
Answer:
The answer is A (the air being heated by the sun)
Explanation:
A P E X
KFell Fe"(CN), + e + Nat → KNaFe'Fe(CN)6
Fe'l. [Fe(CN)6]z + 4e + 4Na+ Na Fe",[Fe''(CN)613
2NH3 + 60H
N2 + 6H2O + 6e
->
What are the reactants in this reaction? What are the products?
Answer:
Most common oxidation states: +2, +3
M.P. 1535º
B.P. 2750º
Density 7.87 g/cm3
Characteristics: Iron is a gray, moderately active metal.
Characteristic reactions of Fe²⁺ and Fe³⁺
The [Fe(H2O)6]3+ ion is colorless (or pale pink), but many solutions containing this ion are yellow or amber-colored because of hydrolysis. Iron in both oxidation states forms many complex ions.
Aqueous Ammonia
Aqueous ammonia reacts with Fe(II) ions to produce white gelatinous Fe(OH)2, which oxidizes to form red-brown Fe(OH)3:
Fe2+(aq)+2NH3(aq)+3H2O(l)↽−−⇀Fe(OH)2(s)+2NH+4(aq)(1)
Fe3appt.gif
Aqueous ammonia reacts with Fe(III) ions to produce red-brown Fe(OH)3:
Fe3+(aq)+3NH3(aq)+3H2O(l)↽−−⇀Fe(OH)3(s)+3NH+4(aq)(2)
Fe3bppt.gif
Both precipitates are insoluble in excess aqueous ammonia. Iron(II) hydroxide quickly oxidizes to Fe(OH)3 in the presence of air or other oxidizing agents.
Sodium Hydroxide
Sodium hydroxide also produces Fe(OH)2 and Fe(OH)3 from the corresponding oxidation states of iron in aqueous solution.
Fe2+(aq)+2OH−(aq)↽−−⇀Fe(OH)2(s)(3)
Fe4appt.gif
Fe3+(aq)+3OH−(aq)↽−−⇀Fe(OH)3(s)(4)
Fe4bppt.gif
Neither hydroxide precipitate dissolves in excess sodium hydroxide.
Potassium Ferrocyanide
Potassium ferrocyanide will react with Fe3+ solution to produce a dark blue precipitate called Prussian blue:
K+(aq)+Fe3+(aq)+[Fe(CN)6]4−(aq)↽−−⇀KFe[Fe(CN)6](s)(5)
Fe5a1ppt.gif
With Fe2+ solution, a white precipitate will be formed that will be converted to blue due to the oxidation by oxygen in air:
2Fe2+(aq)+[Fe(CN)6]4−(aq)↽−−⇀Fe2[Fe(CN)6](s)(6)
Fe5a2ppt.gif
Many metal ions form ferrocyanide precipitates, so potassium ferrocyanide is not a good reagent for separating metal ions. It is used more commonly as a confirmatory test.
Potassium Ferricyanide
Potassium ferricyanide will give a brown coloration but no precipitate with Fe3+. With Fe2+, a dark blue precipitate is formed. Although this precipitate is known as Turnbull's blue, it is identical with Prussian blue (from Equation 5).
K+(aq)+Fe+2(aq)+[Fe(CN)6]3−(aq)↽−−⇀KFe[Fe(CN)6](s)(7)
Fe5b.gif
Potassium Thiocyanate
KSCN will give a deep red coloration to solutions containing Fe3+:
Fe+3(aq)+NCS−(aq)↽−−⇀[FeNCS]+2(aq)(8)
Fe5cppt.gif
No Reaction
Cl−, SO2−4
Which of these is most likely made of pieces of rock that are weathered by water and wind?
O A diamonds
OB sand
OC grass
OD vegetables
Answer:
The answer would be sand.
Explanation:
Sand is weathered down tiny pieces of rock. Sand flows down rivers to shores and slowly builds up to form beaches.
Answer:
The Answer is gonna be B sand
A buffer solution is 0.439 M in CH3COOH and 0.311 M in CH3COONa . If K_a for CH2COOH is 1.8x10^-5, what is the pH of this
buffer solution?
Please no link answers!
Answer:
whats CH3COOH please tell me so I can answer!
What is the elevation of Point B?
A. 800 ft
B. 900 ft
C. 850 ft
D. 1000 ft
Draw the major organic product formed in the reaction. (The reaction stoichiometry is 1 mol reactant: 1 mol Br2 .)
Answer:
Explanation:
The treatment of aldehyde or ketone in the presence of acetic acid with one mole of bromine results in ∝-halo aldehyde or ketone. However, the bromination of ketone undergoes acidic conditions. Hence, the reaction of the ketone with Bromine resulting in the Major Product is shown in the image attached below.
PLEASE HELPP!
a 55g block of metal has a specific heat of 0.45 J/g°C. What will be the temperature change of this metal if 450 J of heat energy are added?
Answer:
18.18 C
Explanation:
m=55
C=0.45
Q=450zj
ch.temp=?
Q=mct
450 = (55)(.45)T
450 = 24.75
/24.75 = /24.75 (cancels out)
18.18 is the answer
A wave travels at 22 m/s and has a wavelength of 11 m. What is its frequency
The answer is 2Hz
To calculate frequency, divide the number of times the event occurs by the length of time.
a freshwater stream flows into the ocean as shown in the diagram which statement correctly describes how the stream affects these salinity of the ocean
A- salinity increases because the stream adds salt to the ocean.
B- salinity decreases because the stream adds freshwater to the ocean
C- salinity increases because of stream adds freshwater to the ocean
D- salinity Remains the Same because the stream adds freshwater to the ocean
2. Given the following equation: 2 KCIO3 ---> 2 KCl + 3 O2
How many moles of O2 can be produced by letting 12.00 moles of KClO3 react?
show work. helppp asap
Answer:
18 moles of O2 can be produced by letting 12.00 moles of KClO3 react
Explanation:
The balanced equation is
2KCIO3 ---> 2 KCl + 3 O2
As per the reaction,
2 mole of KClO3 produces 3 mole of O2 gas
Hence, 12 moles of KClO3 will produce [tex]12*\frac{3}{2} =18[/tex]
Hence, 18 moles of O2 can be produced by letting 12.00 moles of KClO3 react
a solution of KCl in water has a concentration of 0.243 M. The solution has a volume of 0.580 L. How many grams of KCl are present in the solution?
Answer:
10.5 g
Explanation:
Step 1: Given data
Molar concentration of the solution (C): 0.243 MVolume of solution (V): 0.580 LStep 2: Calculate the moles of solute (n)
Molarity is equal to the moles of solute divided by the liters of solution.
M = n/V
n = M × V
n = 0.243 mol/L × 0.580 L = 0.141 mol
Step 3: Calculate the mass corresponding to 0.141 moles of KCl
The molar mass of KCl is 74.55 g/mol.
0.141 mol × 74.55 g/mol = 10.5 g
Plz answer the first two questions and maybe the third. I will give brainliest.
Answer:
1. 24.45 moles
2. 437.90 grams
Bonus :
0.75 grams
Explanation:
Hope it was helpful ;)
1. When there is light, photosynthesis can
A. occur, in the chloroplast.
B. not occur, and the stomata will not be open.
C. not occur, and the stomata will be open.
D. occur, in the
mitochondria.
Answer:
A
Explanation:
Answer:
A. occur, in the chloroplast.
Explanation:
Photosynthesis occur in chloroplasts, with the help of sunlight. Where mitochondria help in respiration
What volume is occupied by 22.1 g of O2 at 52°C and a pressure of 1.63 atm?
Many diseases can be prevented with a proper diet, exercise, and abstinence from smoking, alcohol, drugs, and sexual activity. True or False( Explain)
Answer:
TrueExplanation:
This is due to multiple reasons. First of which, proper diet with a variety of selection of foods from vegetables, to dairy and meats can provide the body with essential nutrients used to fight off diseases and germs and improve the immune system. Exercise can also help boost the immune system and prevent diseases as well. It can also improve the condition of the heart which prevents heart disease and help the brain (prevent strokes). Drugs, smoking, alcohol and unsafe sexual activity can lead to a multitude of diseases, such as lung cancer, drug addictions, cardiac arrest, blood clots, HIV and other STDs, liver failure, etc. So it would be wise to abstain from those activities.
POINTSSS AND BRAINLIEST IF YOU ANSWER CORRECTLY!!! Write about the law of conservation of energy and where light energy goes. thank you :)
Answer:
The law of conservation of energy states that the total energy is constant in any process. Energy may change in form or be transferred from one system to another, but the total remains the same.
Could you please help me with the two most recent questions of mine on my page? I will give u brainliest and 20 points! :))) X
Material use make car tyres and chewing gum?
Answer:
Rubber
Rubber
Make me brainlyist
Which of the following astronomical bodies would most likely be the largest?
1. A dwarf star from a nearby solar system
2. A comet
3. One of the gas giants in our solar system
4. Ganymede, the largest moon of Jupiter
Answer:
1
because a dwarf star will seemlarge because of the in ability of any human being to see d sun
The nucleus inside a eukaryotic cell has ________ that contains cell's DNA.
A. bacteria
B. chromosomes
C. electron
O D. hair
How many grams are in 1.5 moles of oxygen (O2)?
true or false atoms can be made up of just one type of atom
Answer:
false
Explanation:
A compound has the combined properties of the elements from which it is made. Atoms show the macro properties of an element.
BRAINLIEST if answered correctly
Answer:
I would choose E
Explanation:
Chemical reactions occur when chemical bonds between atoms are formed or broken. The substances that go into a chemical reaction are called the reactants, and the substances produced at the end of the reaction are known as the products
web-
10. Although lidocaine is marketed as its hydrochloride salt, it doesn’t exhibit the same level of physiological activity as the free amine. The free amine is more lipophilic and diffuses across a neuron cell membrane more rapidly than the ionic salt, resulting in a more rapid onset of anesthesia. Therefore, sodium bicarbonate (NaHCO3) is added to a solution of lidocaine prior to injection. How does the addition of sodium bicarbonate promote a faster anesthetic effect?
Answer:
Bicarbonate neutralizes the acidity of Lidocaine and hence reduce the pain
Explanation:
Alkalinization by addition of sodium bicarbonate causes buffering of local anesthetics and hence produce faster anesthetic effect such as pain control, pain reduction while injecting the patient and faster onset of local anesthetics.
Lidocaine along with epinephrine results into acidic compound wit respect to subcutaneous tissue. Hence, when bicarbonate is added, it neutralizes the acidity of Lidocaine and hence decrease the pain.
3.
Why do you suppose internet service costs a lot of money?
Answer:
Why does internet cost so much? Equipment and installation: One of the main reasons for internet prices to run high is the cost of equipment and installation in new service areas. Fiber optic cables are expensive, so fiber optic internet providers may have higher prices to recoup the costs of installing new lines.Apr 21, 2021Explanation:
(2pts) Post-lab Questions (1pts) 1. Do you expect the solubility of Borax to increase or decrease as temperature increases? Select the option that best explains why. Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger. Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get smaller. Solubility will decrease, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get smaller. Solubility will decrease, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger. Choose... (1pts) 2. Why was it necessary to make sure that some solid was present in the main solution before taking the samples to measure Ksp? Select the option that best explains why. To make sure no more sodium borate would dissolve in solution. To ensure the dissolution process was at equilibrium. To make sure the solution was saturated with sodium and borate ions. All of the above
Answer:
1. Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger.
2. To ensure the dissolution process was at equilibrium.
Explanation:
Given that;
ΔG°= -RTlnK
and
ΔG° = ΔH° - TΔS°
So;
-RTlnK = ΔH° - TΔS°
lnK = ΔH°/-RT - TΔS°/-RT
lnK = -(ΔH°/RT) + ΔS°/R
K = e^-(ΔH°/RT) + ΔS°/R
Hence, Solubility will increase, because as T increases the − Δ H ∘ R T −ΔH∘RT term becomes smaller therefore K will get larger.
2.
Since solubility is an equilibrium process, it means that some undissolved solute must be present in order to determine the solubility product correctly.
Solubility is the ability of the solute to dissolve in the solution. As temperature increases, the solubility increases, and the presence of solid ensure dissolution.
What is Gibbs energy?The Gibbs free energy is the change in the energy of a system from the energy present in the reactant towards the product formation.
It is given as,
[tex]\rm \Delta G^{\circ}= \rm -RTlnK \\\\\rm \Delta G ^{\circ} = \Delta H ^{\circ} - T\Delta S ^{\circ}[/tex]
Equating both equations we get:
[tex]\begin{aligned} \rm -RTlnK &= \rm \Delta H ^{\circ} - T\Delta S ^{\circ}\\\\\rm lnK &=\rm -(\dfrac{\Delta H ^{\circ}}{RT}) + \dfrac{\Delta S ^{\circ}}{R}\\\\\rm K &=\rm e^{-(\frac{\Delta H ^{\circ}}{RT}) + \frac{\Delta S ^{\circ}}{R}}\end{aligned}[/tex]
Thus, the solubility of the substance increases with an increase in temperature.
The solubility product is estimated correctly by the equilibrium process that ensures the presence of the undissolved solute particles.
Therefore, 1. option A. solubility increases and 2. option B. to ensure the equilibrium process are the correct options.
Learn more about solubility here:
https://brainly.com/question/14092287
Q3: Match the column A with Column B and write answer in Column C
Answer:
ok
Explanation:
1d
2c
3b
4a
Metals are cunductor of heat and electricity prove this statement
Answer:Metals are an excellent conductor of electricity and heat because the atoms in the metals form a matrix through which outer electrons can move freely. Instead of orbiting their respective atoms, they form a sea of electrons that surround the positive nuclei of the interacting metal ions.
Explanation:
It takes 53.0 J to raise the temperature of an 11.0 g piece of unknown metal from 13.0∘C to 24.3 ∘C. What is the specific heat for the metal?
Answer:
Heat absorbed = mS△T
51 = ( 8.2/1000)Kg ×S (11.5)
51×1000= 8.2 (11.5)S
S = 51000/94.3
S = 540.8 J/kg K
Which option correctly matches the chemical formula of a compound with its
name?
A. N20, nitrogen dioxide
B. NO2, nitrogen dioxide
C. N20, dinitrogen dioxide
D. NO2, dinitrogen oxide
Answer:
B. NO₂, nitrogen dioxide
Explanation:
Nitrogen dioxide is one of the oxides of nitrogen. It reacts highly and is very harmful for the health of humans. It is regarded as one of the pollutants of the air pollution. The chemical formula of Nitrogen dioxide is NO₂. This gas is produced during the manufacturing of the fertilizers in the industries. Burning of the fossil fuels also contribute in the emission of nitrogen dioxide. Two atoms of oxygen when reacts with one atom of Nitrogen, Nitrogen dioxide is formed.