Answer:
Okay
Explanation:
2a Define Radioactivity?
Answer:
The emmision of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei
or
the giving off of rays of energy or particles by the breaking apart of atoms of certain elements
a. Explain why bicycle tires seem higher in the summer than in winter.
b. Explain why a can of soda pop explodes if left in the hot sun.
c. A rigid container filled with a gas is placed in ice (ex. nalgene bottle). What will happen to the pressure of the gas? What do you think will happen to the volume?
d. An infected tooth forms an abscess* that fills with gas. The abscess puts pressure on the nerve of the tooth, causing a toothache. While waiting to see a dentist, the person with the toothache tried to relieve the pain by treating the infected area with moist heat. Will this treatment help? Why or why not?
Answer:
a) When air inside the tires gets colder, it shrinks, so the tires seem flat, even though they haven't lost any air.
b) When the air inside the soda can gets hot, the molecules of gas move faster, exerting more and more and more pressure, eventually exploding the soda can.
c) When the nalgene is cooled, the air pressure inside will lower; the volume of the nalgene will stay the same, though, because the nalgene is a rigid container.
Which description best matches Rutherford's model of the atom?
Group of answer choices
A The atoms is a positive sphere with negative electrons embedded in it.
B Electrons orbit the nucleus in set, circular orbits.
C The atoms has a tiny, massive nucleus at its center with electrons surrounding it
D The atoms is a solid, indivisible sphere
Answer:
C The atoms has a tiny, massive nucleus at its center with electrons surrounding it
Explanation:
From the experiment by Rutherford, he suggested a model of the atom where there is a tiny but massive nucleus at the center with electrons surrounding it.
Rutherford found that most of the alpha particles in his gold foil experiment pass through but a few were deflected back. He suggested an atomic model to explain his observation. In this model, the atom has small positively charged center where the mass of the atom is concentrated. Surrounding the nucleus is a large space containing the electrons.35 POINTS Y'ALL
What is the difference in petroleum and natural gas?
thanks,
-throckmorton
Answer:
:)
Explanation:
Petroleum gas is mainly C3 and C4 based (propane and butane), whilst natural gas is predominantly C1 and C2 (methane and ethane). Petroleum gas is generally produced via the cracking of naphtha, which is one of the components separated during crude oil refining.
Petroleum is C3 or C4 (propane and butane) while Natural Gas is C1 and C2. (methane and ethane)
Petroleum is also produced differently then Natural Gas.
"Petroleum gas is generally produced via the cracking of naphtha, which is one of the components separated during crude oil refining." - socratic.org
what has a higher melting point KBr or CH3CH2CH2CH3
Answer:
i don't understand the question
Explanation:
Has a definite volume and shape
Answer:
If you're talking about Solid, Liquid, and Gas the answer would be... well I'm not gonna give this to you straiight away but, here's a game! It has at least 5 letters in it...It has the letter I in it, It has a S in it Hope you got the answer! ✨Brainliest pwease!
Calculate the theoretical yield of aspirin obtained when 2.0 g of salicylic acid and 5.0 mL of acetic anhydride (density = 1.08 g/mL) 2. if 1.9 g f asprin were obtained in this experiment, what would be the percent yield?
Answer:
The percent yield would be 73%
Explanation:
The balanced reaction for the obtention of acetylsalicylic acid (aspirin) is the following:
Salicylic acid + acetic anhydride → acetylsalicylic acid + acetic acid
C₇H₆O₃ + C₄H₆O₃ → C₉H₈O₄ + C₂H₄O₂
According to the reaction, 1 mol of salicylic acid reacts with 1 mol of acetic anhydride to give 1 mol of acetylsalicylic acid (aspirin) and 1 mol of acetic acid.
1 mol aspirin (C₉H₈O₄) = (9 x 12 g/mol) + (8 x 1 g/mol) + (4 x 16 g/mol)
= 180 g
1 mol salicylic acid (C₇H₆O₃) = (7 x 12 g/mol) + (6 x 1 g/mol) + (3 x 16 g/mol)
= 138 g
1 mol acetic anhydride (C₄H₆O₃) = (4 x 12 g/mol) + (6 x 1 g/mol) + (3 x 16 g/mol)
= 102 g
The stoichiometric ratio is = 138 g salicylic acid/102 g acetic anhydride= 1.35
We have:
2.0 g salicylic acid
acetic anhydride = 5.0 mL x 1.08 g/mL = 5.4 g
The reactants ratio is = 2.0 g salicylic acid/5.4 g acetic anhydride = 0.37
0.37 < 1.35 , therefore salicylic acid is the limiting reactant.
Now, we use the amount of salicylic acid to calculate the theoretical amount of aspirin. For this, we know that 1 mol of aspirin (180 g) is obtained from 1 mol of salycilic acid (138 g):
theoretical yield= 180 g aspirin/138 g salycilic acid x 2.0 g salycilic acid = 2.61 g aspirin
actual yield = 1.9 g
Finally, we calculate the yield:
percent yield = actual yield/theoretical yield x 100
= 1.9 g/2.6 g x 100 = 72.8% ≅ 73%
A heliox deep-sea diving mixture contains 2.0 gg of oxygen to every 98.0 gg of helium. What is the partial pressure of oxygen when this mixture is delivered at a total pressure of 8.0 atm?
Answer:
The correct answer is 0.020 atm.
Explanation:
Partial pressure is calculated by using the formula,
Partial pressure = Mole fraction × Total pressure
The partial pressure of oxygen in a mixture can be calculated by using the formula,
Mole fraction of oxygen in mixture = Number of moles of oxygen / No. of moles of oxygen + No. of moles of Helium
(1 gg or gigagram is equal to 10⁹ grams)
= 2 × 10⁹/32 /2 × 10⁹/32 + 98 × 10⁹ / 4
= 2.54 × 10⁻³
Now the partial pressure of oxygen = Mole fraction of oxygen × Total pressure of oxygen
= 2.54 × 10⁻³ × 8.0 atm
= 0.02032 atm
= 0.020 atm
A sample of Br2 gas has a volume of 29.0L and a pressure of 1.50 atm. If the initial temperature of the gas is 23 °C, what volume, in liters, will the gas occupy at 3.50 atm and 271 °C?
Answer:
V₂ = 22.84 L
Explanation:
Given data:
Initial volume = 20.0 L
Initial pressure = 1.50 atm
Initial temperature = 23 °C (23 +273 = 296 K)
Final temperature = 271°C (271+273 = 544 K)
Final pressure = 3.50 atm
Final volume = ?
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 1.50 atm × 29.0L ×544 K / 296 K × 3.50 atm
V₂ = 23664 atm .L. K / 1036 atm.K
V₂ = 22.84 L
In the reaction, 2HgO(s)⟶2Hg(s) O2(g). How many liters of oxygen, O2 measured at STP, would be produced from the decomposition of 111 g of mercury(II) oxide, HgO?
Answer:
5.74 L O₂
General Formulas and Concepts:
Chemistry - Gas Laws
Reading a Periodic TableUsing StoichiometrySTP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 KExplanation:
Step 1: Define
RxN: 2HgO (s) → 2Hg (s) + O₂ (g)
Given: 111 g HgO
Step 2: Identify Conversions
STP
Molar Mass of Hg - 200.59 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of HgO - 200.59 + 16.00 = 216.59 g/mol
Step 3: Stoichiometry
[tex]111 \ g \ HgO(\frac{1 \ mol \ HgO}{216.59 \ g \ HgO} )(\frac{1 \ mol \ O_2}{2 \ mol \ HgO} )(\frac{22.4 \ L \ O_2}{1 \ mol \ O_2} )[/tex] = 5.73988 L O₂
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
5.73988 L O₂ ≈ 5.74 L O₂
1+1 hahahahahhhahahaahahahahahahahahahahahahahaha why u dumb
Answer:
1+1=2 Unless this is a trick question. Then it's most likely 11.
Explanation:
1 + 1 = 2
thxs for the points realy tho thxs
A sample contains 16 mg of polonium-218. After 12 minutes, the sample will contain 1.0 mg of polonium-218. What is the half life of polonium-218?
Answer:
Half-life = 3 minutes
Explanation:
Using the radioactive decay equation we can solve for reaction constant, k. And by using:
K = ln2 / Half-life
We can find half-life of polonium-218
Radioactive decay:
Ln[A] = -kt + ln [A]₀
Where:
[A] could be taken as mass of polonium after t time: 1.0mg
k is Reaction constant, our incognite
t are 12 min
[A]₀ initial amount of polonium-218: 16mg
Ln[A] = -kt + ln [A]₀
Ln[1.0mg] = -k*12min + ln [16mg]
-2.7726 = - k*12min
k = 0.231min⁻¹
Half-life = ln 2 / 0.231min⁻¹
Half-life = 3 minutesA concentration cell is one in which both the anode and cathode are the same but with different concentrations. Calculate the cell potential with [Zn2+] = 0.10 M for the cathode and the [Zn2+] = 0.010 M for the anode?
Answer:
The cell potential = +0.03 V
Explanation:
The half reactions for the cells are given below:
Oxidation half reaction (anode): Zn(s) ----> Zn²⁺(aq) + 2e⁻
Reduction half reaction (cathode): Zn²⁺(aq) + 2e⁻ -----> Zn(s)
To calculate cell potential of the cell, we use the equation given by Nernst, which is given as: Ecell = E°cell - (0.0591/n) log Q
where Q = Concentration of dilute solution/Concentration of concentrated solution = 0.01/0.1
n = number of moles of electrons transferred = 2
Since, the cell is a concentration cell, E°cell = 0
therefore, the Nernst equation becomes, Ecell = - (0.0591/n) log Q
substituting the values;
Ecell = - (0.0591/2) log (0.01/0.10)
Ecell = +0.03 V
Therefore, the cell potential = +0.03 V
How long will it take to deposit 6.32 g of copper from a CuSO4(aq) solution using a current of 0.554 amps
Answer:
34672.96 s
Explanation:
m = Mass of copper = 6.32 g
M = Molar mass of copper = 63.5 g/mol
F = Faraday constant = 96500 C/mol
The electrode equation would be
[tex]Cu^{2+}(aq)+2e^{-}=Cu(s)[/tex]
Number of electrons = 2 = e
I = Current = 0.554 A
t = Time taken
Charge would be
[tex]Q=\dfrac{m}{M}eF\\\RightarrowQ=\dfrac{6.32}{63.5}\times 2\times 96500\\\Rightarrow Q=19208.82\ \text{C}[/tex]
Charge is given by
[tex]Q=It\\\Rightarrow t=\dfrac{Q}{I}\\\Rightarrow t=\dfrac{19208.82}{0.554}\\\Rightarrow t=34672.96\ \text{s}[/tex]
Time taken to deposit the copper is 34672.96 s.
Who ever does this, get brainiest.
Answer:
C.
Explanation:
They will need to know the influence of gravitational force on objects because gravity can affect an objects weight.
What factors affect the strength of the electromagnet?
Factors that affect the strength of electromagnets are the nature of the core material, strength of the current passing through the core, the number of turns of wire on the core and the shape and size of the core.
Answer:
an effect could be that the battery could be running out of juice or that there isnt enough wire on a nail on the electromagnet.
Explanation:
Study the image. Earth showing air mass movement. Purple and red arrows are moving in a counterclockwise direction. Based on the arrows, in which direction are air masses moving? from west to east from north to south toward the equator toward the middle latitude
Answer:
A
Explanation:
Based on the arrows, the direction the air masses are moving is from west
to east.
What are Air masses?These contains large volume of air which has a uniform temperature and
humidity. Air masses move in the atmosphere through the process known
as Convection.
The movement of the air tells us that the movement is from the Western
part to the Eastern part of the atmosphere.
Read more about Air masses here https://brainly.com/question/440479
Calculate the average kinetic and potential energies of a 2s electron in a hydrogenic atom of atomic number Z.
Answer:
z = 2s
Explanation:
This is the only info given.
Identify at least 5 pure substance found in nature,in the supermarket, grocery storeand even at your home.use the table below to explain your answer based on appearance, separating technique, boiling and melting point.
Answer:
Explanation:
1) Pure substance: Water (found at home)
Appearance: It is homogeneous since it is a single substance that appears as liquid. Homogeneous is when the components of a substance are in a single phase
Separating technique: It's component cannot be separated by physical means
Boiling point: Water boils at 100 °C
Melting point: Water melts/freezes at 0°C
2) Pure substance: Table salt (found at home)
Appearance: It is also homogeneous as it is a single substance that is solid. Separating technique: It's component cannot be separated by physical means
Boiling point: Water boils at 1,465 °C
Melting point: Water melts/freezes at 801 °C
3) Pure substance: Butter (found at home and grocery store)
Appearance: It is homogeneous even though it contains different components
Separating technique: It's component can be separated by physical means since butter is an emulsion of fat in water. The 15% water content can be evaporated/distilled out at 100 °C
Boiling point: Butter starts boiling at about 110-120 °C
Melting point: It melts at about 37 °C
4) Pure substance: Candle (wax) (found at home and grocery store)
Appearance: It is homogeneous
Separating technique: It's component cannot be separated by physical means
Boiling point: It starts boiling around 370 °C
Melting point: It melts at about 37 °C
5) Pure substance: table sugar/sucrose (found at home, grocery stores and in supermarkets)
Appearance: It is homogeneous
Separating technique: It's component cannot be separated by physical means
Boiling point: It starts boiling around 697 °C
Melting point: It melts at about 186 °C
A pure substance is an homogeneous material, having a composition, and
properties that are consistent through out the material.
The chemical properties of a pure substance are defined, such as the
products of its reaction can be predictable.
A chemical is pure when it consist of a single type of particle such as an
element, a molecule or a compound.
The five pure substances are presented as follows;
[tex]\displaystyle\begin{tabular}{|l|l|l|l|l|}\underline{Pure \ Substances}&\underline{Appearance}&\underline{Separaing Tech}&\underline{Boiling \ Point}&\underline{Melting \ point}\\1. Diamond&Translucent \ solid&Inseparable&3550^{\circ}&4830^{\circ}\\2. Table \ salt&White\ crystals&Insepble&801^{\circ}&1413^{\circ}\\3. Water&Tran parent \ liquid&Insepble&0^{\circ}&100^{\circ}\\4. Sugar&Whilte \ crystals&Heating&Decomposes&186^{\circ}\\5. Gold&Yellowish \ metal&Inseparable& 2700^{\circ}&1064^{\circ}\end{array}[/tex]
Learn more here:
https://brainly.com/question/18349770
A aliquot of solution containing of in required of EDTA solution for titration. How many milligrams of will react with of this EDTA solution?
Answer:
The answer is "[tex]\bold{1.39 \ mg}[/tex]".
Explanation:
Please find the complete question in the attached file.
Total Moles of [tex]Mg_2^{+}[/tex] = moles of [tex]MgSO_4[/tex]
[tex]= \frac{mass}{molar \ mass \ of MgSO_4}\\\\= \frac{0.450}{120.37}\\\\ = 0.0037385 \ mol[/tex]
[tex]Mg_2^{+} + EDTA4^{-} \longrightarrow Mg(EDTA)2^{-}[/tex]
EDTA mol in 37.6 mL of solution = 50.0 mL of [tex]Mg2^{+}[/tex]
[tex]= \frac{50.0}{500} \times[/tex] total moles of [tex]Mg2^{+}[/tex]
[tex]= \frac{50.0}{500} \times 0.0037385\\\\= 3.7385 \times 10^{(-4)} \ mol\\[/tex]
[tex]Ca2^{+} + EDTA4^{-} \longrightarrow Ca(EDTA)2^{-}[/tex]
[tex]CaCO_3 Moles = Ca2^{+} Moles =[/tex] EDTA moles in a solution of 1.40 mL
[tex]= \frac{1.40}{37.6} \times 37.6 \ mL[/tex] the solution of EDTA moles.
[tex]= \frac{1.40}{37.6} \times 3.7385 \times 10^{(-4)} \\\\= 1.392 \times 10^{(-5)}\ mol\\\\[/tex]
Mass of [tex]CaCO_3 =[/tex]mole[tex]\times[/tex] the molar mass of [tex]CaCO_3[/tex]
[tex]= 1.392 \times 10^{(-5)} \times 100.09\\\\= 0.00139 \ g\\\\ = 1.39 \ mg[/tex]
iron chloride + sodium hydroxide
Answer:
Sodium hydroxide reacts with iron(III) chloride to produce iron(III) hydroxide and sodium chloride.
Hope this helps plz hit the crown :D
In a titration of monoprotic acids and bases, there is a large change in pHA. at the point where pH = pKa of the acid.B. when the volume of acid is exactly equal to the volume of base.C. when the concentration of acid is exactly equal to the concentration of base.D. when the number of moles of acid is exactly equal to the number of moles of base.E. at the point where pH = pKb of the
Answer:
D. when the number of moles of acid is exactly equal to the number of moles of base.
Explanation:
Regarding options A. and E., pKa and pKb would only be taken into consideration if the titrations were of weak acids and bases. However it is possible to have a titration of monoprotic acids and bases with strong acids and bases.
Another way of looking at the answer is identifying which one best describes the equivalence point.
What is electronegativity and which chemical family has
the strongest electronegativity according the the Periodic
Trends?
Answer:
Of the main group elements, fluorine has the highest electronegativity (EN = 4.0) and cesium the lowest (EN = 0.79). This indicates that fluorine has a high tendency to gain electrons from other elements with lower electronegativities.
Explanation:
the position-time graph shows the motion of four people. label the lines on graph need on the motion description in this table.
Answer:
4,2,3,1
Explanation:
A seawater sample contains 2.7 mg chl [tex]m^{-3}[/tex]. What is the chlorophyll concentration in units of mg [tex]L^{-1}[/tex]?
Given :
A seawater sample contains 2.7 mg chlorophyll m⁻³.
To Find :
What is the chlorophyll concentration in units of mg L⁻¹.
Solution :
We know, 1 m³ = 1000 L .
So, 1 m⁻³ = 10⁻³ L⁻¹
Concentration is :
[tex]c = 2.7\ mg\ m^{-3}\\\\c = 2.7\times 10^{-3}\times \ mg\ L^{-1}\\\\c = 0.0027 \ mg\ L^{-1}\\\\c = 2.7\ \mu g \ L^{-1}[/tex]
Therefore, the chlorophyll concentration in units of mg L⁻¹ is [tex]2.7\ \mu g \ L^{-1}[/tex].
Hence, this is the required solution.
1. How many Chromium atoms are found in 25.8 milligrams of Chromium?
Answer: 51.9961 g/mol, don't know if it helps :)
Explanation:
Answer:
Chromium is a steel-gray, lustrous, hard metal that takes a high polish, is fusible with difficulty, and is resistant to corrosion and tarnishing.
The most common oxidation states of chromium are +2, +3, and +6, with +3 being the most stable. +4 and +5 are relatively rare. Chromium compounds of oxidation state 6 are powerful oxidants.ion:
Which of the following statements explain how creativity leads to new investigations? Check all of the boxes that apply.
Creativity lets scientists use their imagination to invent results.
Creativity leads scientists to design new methods to test their hypotheses.
Creativity allows scientists to investigate untestable hypotheses.
Creativity permits scientists to think of new questions to investigate.
Answer:
Creativity leads scientists to design new methods to test their hypotheses.
Creativity permits scientists to think of new questions to investigate.
Explanation:
A scientist must be very creative and must be a critical thinker.
Creativity is the ability of someone to use imaginations to solve a problem.
It is the art of being inventive. To the scientific world, creativity is very essential. It helps scientists to design new methods to validate their hypothesis. It also helps to bring up new questions that might be investigated.Answer:
B and D
Explanation:
Write the balanced equation for the neutralization reaction between H3PO4 and NaOH in an aqueous solution.
Answer:
H3PO4 + 3NaOH ==> Na3PO4 + 3H2O
The balanced equation for the given reaction is [tex]3NaOH+H_3PO_4---- > Na_3PO_4+3H_2O[/tex]
What is neutralization reaction?A chemical reaction in which an acid and a base react quantitatively with each other is known as neutralization.
In a water reaction, neutralization means that there is no excess of hydrogen or hydroxide ions in the solution.
A neutralization reaction occurs when an acid and a base react to form water and a salt through the combination of H+ ions and OH- ions. The pH of neutralization of a strong acid and a strong base is 7.
Three moles of sodium hydroxide are required for one mole of phosphoric acid. The balanced equation tells us the following: 1 mol of H3PO4 reacts with 3 mol of NaOH.
It can be written as
[tex]3NaOH+H_3PO_4---- > Na_3PO_4+3H_2O[/tex]
Thus, this is the balanced equation for the given neutralizing reaction.
For more details regarding neutralization reaction, visit:
https://brainly.com/question/20038776
#SPJ2
What is the difference between Mega and Milli symbols?
Answer:
Mega = 10^6
Milli = 10^-3
Explanation:
Mega is whatever times 10 to 6th power.
Milli is whatever times 10 to the -3rd power.
The pressure of a compressed gas is 1.45 atm. What is this pressure in kPa
Answer:
1.45 Atmospheres = 146.92125 Kilopascals, or about 146.9 Kilopascals
Explanation:
1 Atmosphere = 101.325 Kilopascals, so 101.325 Kilopascals x 1.45 Atmospheres = 146.92125 Kilopascals.
Using the conversion table, the pressure of the compressed gas at 1.45 atm when converted to kilopascal becomes 146.92 kPa.
How to convert from atm to kPa?
Atm is the standard atmosphere which is a unit of pressure.
From conversion table
1 atm atmospheric pressure is equivalent to 101.325 kPa ( kilopascal ).
Now, the pressure of the compressed gas at 1.45 atm will be;
P = 1.45 × 101.325 kPa
P = 146.92 kPa
Therefore, the pressure of the compressed gas at 1.45 atm when converted to kilopascal using the conversion table becomes 146.92 kPa.
Learn more about atmospheric pressure here: https://brainly.com/question/13407492
#SPJ2