Answer:
0.015 M
Explanation:
For a first order reaction;
ln[A] =ln[A]o - kt
[A] = final concentration
[A]o =initial concentration
k= rate constant
t= time taken
ln[A] =ln[A]o - kt
ln[A] = ln(0.0500) - 6.7 x 10-4 (30 × 60)
ln[A] = -2.9957 - 1.206
ln[A] = -4.202
e^ln[A] = e^(-4.202)
A= 0.015 M
c6h5-c=o-ch3 + br2/oh
Explanation:
here's the molecule you were looking for
Which best describes a scientist who solves a new problem using something already learned?
creative
curious
observant
skeptical
Answer:
The answer should be Skeptical
State Newton second law
202H8(9) + 7 O2(g) > 4CO2(g) + 6 H2O(9).
AH = -1560.7 kJ/mol
Which direction with the equilibrium shift if the carbon dioxide is increased?
since the concentration of Carbon Dioxide will increase, it would make Q > K, cause equilibrium to shift in the direction with less moles of gas to alleviate the extra pressure. In this case, the reaction will shift left because there are fewer moles of gas present.
pls help!!! How can you prove the pennies are made of different material aside from cutting them in half?
Answer:
Most of our coins are metal sandwiches. The outside layers are three-quarters copper and one-quarter nickel, and the "filling" is solid copper. Pennies are made of zinc coated with copper. Only nickels are one solid material—that same 75% copper/25% nickel alloy
Explanation:
A student isolated an unknown organic compound through extraction. The student measures the melting point and fins it to be 115-122 C. The student looks through the list of possible strucures and decides the comound is most likely 2-napthol. Do you believe this choice is correct?
Name the following alkane molecule:
CH3
|
CH3CHCH2CHCH2CHCH3
CH
CH2CH2CH3
A. 2,4,6-trimethylheptane
B. 4-ethyl-2,6-dimethylheptane
C. 2,6-dimethyl-4-propylheptane
Answer:
2,6dimethyle-4-propylheptane
I guess!
The correct name of the compound is 4-ethyl-2,6-dimethylheptane.
What is IUPAC nomenclature?The IUPAC nomenclature shows the correct way to name a compound this rule is established by the International Union of Pure and Applied Chemistry.
Looking at the structure of the compound as shown, the correct name of the compound is 4-ethyl-2,6-dimethylheptane.
Learn more about IUPAC nomenclature: https://brainly.com/question/14356798
A graph of gas pressure versus the number of particles in a container is a straight line. Which other relationship will have a similar graph?
Answer:
volume versus temperature, because they are also directly proportional.
Explanation:
Just took the test!
A certain polytomic ion contains 49 protons and 50 electrons. What's the net charge of this ion?
Answer:
the charge is -1
Explanation:
because the charge of proton is +and electron -
charge = +49 +(-50)
= -1
Answer:
Net charge is -1
Explanation:
[tex]{ \sf{net \: charge = p {}^{ + } + {e}^{ - } }} \\ = { \sf{49 + ( - 50)}} \\ = - 1[/tex]
The half life of radium-226 is 1600 years. If you have 200 grams of radium today how many grams would be present in 8000 years?
Answer:
Half life is the time taken by a radio active isotope to reduce by half of its original amount. Radium-226 has a half life of 1602 years meaning that it would take 1602 years for a mass of radium to reduce by half.
Number of half lives in 9612 years = 9612/1602 = 6 half lives
New mass = Original mass x (1/2)n where n is the number of half lives.
Therefore, New mass= 500 x (1/2)∧6
= 500 x 0.015625
= 7.8125 g
Hence the mass of radium after 9612 years will be 7.8125 grams.
Explanation:
Answer:
[tex]\boxed {\boxed {\sf 6.25 \ grams}}[/tex]
Explanation:
We are asked to find the mass of a sample of radium-226 after half-life decay. We will use the following formula:
[tex]A= A_o *\frac{1}{2}^{\frac{t}{h}}[/tex]
In this formula, [tex]A_o[/tex] is the initial amount, t is the time, and h is the half-life.
For this problem, the initial amount is 200 grams of radium-226, the time is 8,000 years, and the half-life is 1,600 years.
[tex]\bullet \ A_o= 200 \ g \\\\bullet \ t= 8,000 \ \\\bullet \ h= 1,600[/tex]
Substitute the values into the formula.
[tex]A= 200 \ g * \frac{1}{2} ^{\frac{8.000}{1,600}[/tex]
Solve the fraction in the exponent.
[tex]A= 200 \ g * \frac{1}{2}^{5}[/tex]
Solve the exponent.
[tex]A= 200 \ g *0.03125[/tex]
[tex]A= 6.25 \ g[/tex]
In addition, we can solve this another way. First, we find the number of half-lives by dividing the total time by the half-life.
8,000/1,600= 5 half-livesEvery half-life, 1/2 of the mass decays. Divide the initial mass in half, then that result in half, and so on 5 times.
1. 200 g/2= 100 g2. 100 g / 2 = 50 g3. 50 g / 2 = 25 g 4. 25 g / 2 = 12.5 g5. 12.5 g / 6.25 gAfter 8,000 years, 6.25 grams of radium-226 remains.
The functional groups in an organic compound can frequently be deduced from its infrared absorption spectrum. A compound, C5H10O2, exhibits strong, broad absorption across the 2500-3200 cm^1 region and an intense absorption at 1715 cm'^-1. Relative absorption intensity: (s)=strong, (m)-medium, (w) weak. What functional class(cs) docs the compound belong to List only classes for which evidence is given here. Attach no significance to evidence not cited explicitly. Do not over-interpret exact absorption band positions. None of your inferences should depend on small differences like 10 to 20 cm^1. The functional class(es) of thla compound is(are) alkane (List only if no other functional class applies.) alkene terminal alkyne internal alkyne arene alcohol ether amine aldehyde or ketone carboxylic acid ester nitrile
Answer:The functional groups in an organic compound can frequently be deduced from its infrared absorption spectrum. A compound, C5H10O2, exhibits strong, broad absorption across the 2500-3200 cm^1 region and an intense absorption at 1715 cm'^-1. Relative absorption intensity: (s)=strong, (m)-medium, (w) weak. What functional class(cs) docs the compound belong to List only classes for which evidence is given here. Attach no significance to evidence not cited explicitly. Do not over-interpret exact absorption band positions. None of your inferences should depend on small differences like 10 to 20 cm^1. The functional class(es) of thla compound is(are) alkane (List only if no other functional class applies.) alkene terminal alkyne internal alkyne arene alcohol ether amine aldehyde or ketone carboxylic acid ester nitr
When a marble is dropped into a beamer of water
Answer:
The water will rise.Explanation:
hope this helps you
-Sweety<3The mass of the marble is greater than that of the water. The marble weighs more than an equivalent volume of the water. The force from dropping the marble breaks the surface tension of the water. The marble has greater mass and volume than the water.
What is the amount of heat required to change one mole of a substance from the solid to liquid state known as?
Select the correct answer below:
A) the enthalpy of fusion
B) the melting point
C) the entropy of disorder
D) none of the above
A) the enthalpy of fusion
Explanation:
the heat of vaporization, is the amount of energy needed to change a liquid to a gas at constant temperature and pressure. The energy required to melt a solid to a liquid is called the heat of fusion, and the heat of sublimation is the energy.
Answer:
A
Explanation:
what is the net charge of an ion that as 14 protons 16 electrons and 12 neutrons
Answer:
[tex]\boxed {\boxed {\sf -2}}[/tex]
Explanation:
We are asked to find the net charge of an ion.
The ion has 14 protons, 16 electrons, and 12 neutrons. Recall the charges of each subatomic particle.
Proton: +1 Electron: -1 Neutron: 0Neutrons are neutral and have no charge, so we can ignore them while finding the net charge. There are 14 protons and 16 electrons.
14 protons and 14 electrons have a net charge of 0 because the charges balance each other out. However, we have 16 electrons, which is 2 more than 14. Each electron has a charge of -1, so the 2 electrons add a charge of -2.
The net charge of the ion is -2.
Rubric #2
Forensic Science
1. Define Nucleus.
2. Define Cytoplasm.
3. Define Cell Membrane.
4. Define DNA.
5. Define Plant.
6. Define Chlorophyll.
7. Define Photosynthesis.
8. How do Plant cells and Animal cells differ?
9. Define Cell Wall.
10. Define Vacuole.
11. Why do cells differentiate in multicellular organisms?
12. Define Multicellular.
13. Complete the Eukaryotic cells and Cell Differentiation assessment.
https://clever.discoveryeducation.com/learn/techbook/units/95c20a43-6d3d-40d3-
848d-89929101140d/concepts/co0fef01-33e7-4116-8819.
143e289e15ba/tabs/6e1551ab-57b8-42d4-8e5b-25549791c760/pages/de4182af-aa 60-
454f-ae5e-28df6f4eb3ac
Explanation:
1. Nucleus is a memberane bound organelle that contains cell,s chromosomes.
How many cells don’t match, it should be identical.
Answer:
3 cells don't match, identically
Answer:
3 cells don't match identically
why is repetition important in science?
Answer:
the repetition principle is important in scientific research, because the observational indexes are random variables,which requires a certain amount of samples to reveal their changing regularity
Write chemical equations for the acid-base reactions that occur when:
a. Solutions of HC₂H₃O₂ (acetic acid) and KOH are mixed.
b. Solutions of HCN (hydrocyanic acid) and Na₂CO₃ are mixed.
Acetic acid is basically known as CH_3COOH.
Chemical Equation:-
[tex]\boxed{\sf {CH_3COOH\atop Acetic\:acid}+{KOH\atop Potassium\:Hydroxide}\longrightarrow {CH_3COOK\atop Potassium\: Acetate}+{H_2O\atop Water}}[/tex]
This kinda reaction is called Neutralization Reaction.Solution:-2
[tex]\boxed{\sf {HCN\atop Hydrogen\:Cyanate}+{Na_2CO_3\atop Sodium\:Carbonate}\longrightarrow {NaCN\atop Sodium\:Cyanate}+{H_2O\atop water}+{CO_2\atop Carbon\:dioxide}}[/tex]
Hydro cyanic acid is also called HydrogenCyanate.Write any four difference between metals and non metals.
Answer:
metals are malleable and ductile.
Non metals are non malleable and ductile.
Metals are good conductor of heat and electricity.
Non metals are bad conductor of heat and electricity.
Metals are lustrous.
Non metals are non lustrous.
Metals are strong and tough.
Non metals are not strong or tough.
Hope it helps you.Thank you
Answer:
1metal are good conductor of heat and electricity
2metal are ductile and mellability .
3it doesnot get brittle .
4metal are hard .
and for nonmetle you can just add
Calculate the no. of moles in 15g of CaCl2
Answer:
[tex]\boxed {\boxed {\sf 0.14 \ mol \ CaCl_2}}[/tex]
Explanation:
We are asked to calculate the number of moles of 15 grams of calcium chloride (CaCl₂).
To convert from grams to moles, we use the molar mass, or the mass of 1 mole of a substance. Molar masses are found on the Periodic Table because they are equivalent to the atomic masses, but the units are grams per mole instead of atomic mass units.
Look up the individual elements in the compound: calcium and chloride.
Ca: 40.08 g/mol Cl: 35.45 g/molNotice the chemical formula has a subscript of 2 after Cl or chlorine. There are 2 moles of chlorine in every 1 mole of calcium chloride. We must multiply chlorine's molar mass by 2 before adding calcium's molar mass.
Cl₂: 35.45 * 2 = 70.9 g/mol CaCl₂= 40.08 + 70.9 = 110.98 g/molWe will convert using dimensional analysis, so we must create a ratio using the molar mass.
[tex]\frac {110.98 \ g \ CaCl_2}{ 1 \ mol \ CaCl_2}[/tex]
We are converting 15 grams of calcium chloride to moles, so we must multiply the ratio by this value.
[tex]15 \ g \ CaCl_2 *\frac {110.98 \ g \ CaCl_2}{ 1 \ mol \ CaCl_2}[/tex]
Flip the ratio so the units of grams of calcium chloride cancel.
[tex]15 \ g \ CaCl_2 *\frac { 1 \ mol \ CaCl_2}{110.98 \ g \ CaCl_2}[/tex]
[tex]15 *\frac { 1 \ mol \ CaCl_2}{110.98}[/tex]
[tex]\frac { 15}{110.98} \ mol \ CaCl_2[/tex]
[tex]0.1351594882\ mol \ CaCl_2[/tex]
The original measurement of grams (15) has 2 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place. The 5 in the thousandth place tells us to round the 3 up to a 4.
[tex]0.14 \ mol \ CaCl_2[/tex]
15 grams of calcium chloride is approximately 0.14 moles of calcium chloride.
How does a smoke detector utilize radiation?
A. Beta radiation creates a stead stream of electrons. When the stream is broken by smoke particles, it sets off the alarm.
B. Alpha radiation ionizes the air. When smoke interacts with the ionized particles it causes the alarm to sound.
C. Gamma radiation creates a stead stream of electrons. When the stream is broken by smoke particles, it sets off the alarm.
D. Beta radiation ionizes the air. When smoke interacts with the ionized particles it causes the alarm to sound.
Which gas will have the least collisions between its particles?
A. Argon at 265 K
B. Helium at 20 C
C. Oxygen at -45 C
D. Carbon dioxide at 80 C
Answer:
C
Explanation:
This is because oxygen has the lowest temperature, thereby collision rate is least
If my primary DNA strand is ATACCGCAA
a write the complimentary DNA strand
Answer:
TATGGCGTT
Explanation:
Complimentary base pairs:
A-T
C-G
Use the other letter for complimentary strands
what is a compound?And what are some common examples of a compound?
Answer:
Compounds are substances made from atoms of different elements joined by chemical bonds. Common examples are water (H2O), salt (sodium chloride, NaCl), methane (CH4).
Explain why you get a basic solution when you dissolve NaF in water.
Answer:
The fluoride ion is capable of reacting, to a small extent, with water, accepting a proton. The fluoride ion is acting as a weak Brønsted-Lowry base. The hydroxide ion that is produced as a result of the above reaction makes the solution slightly basic.
So
we get a basic solution when you dissolve NaF in water.
Na is a alkaline earth metal
Metallic compound dissolved in water acts as base
Also there is another reason
Na F is ioniC
Fluorine is known as having highest electron affinity in world
It can accept a line pair of OH-
So it's Bronsted Lowry base .
It can also acts as Arrhenius baseHence its basic
write anode and cathode in Zn-Ag galvanic cell
Explanation:
Zinc is the anode (solid zinc is oxidised). Silver is the cathode (silver ions are reduced).
By convention in standard cell notation, the anode is written on the left and the cathode is written on the right. So, in this cell: Zinc is the anode (solid zinc is oxidised). Silver is the cathode (silver ions are reduced).
If an experiment calls for 0.200mole acetic acid (Hc2H3O2)how many grams of glacial acetic acid do we need?
[tex]\\ \sf\longmapsto HC_2H_3O_2[/tex]
[tex]\\ \sf\longmapsto 1u+2(12u)+3(1u)+2(16u)[/tex]
[tex]\\ \sf\longmapsto 1u+24u+3u+48u[/tex]
[tex]\\ \sf\longmapsto 28u+48u[/tex]
[tex]\\ \sf\longmapsto 76u[/tex]
[tex]\\ \sf\longmapsto 76g/mol[/tex]
No of moles=0.2molGiven mass=?[tex]\\ \sf\longmapsto No\:of\;moles=\dfrac{Given\:Mass}{Molar\:Mass}[/tex]
[tex]\\ \sf\longmapsto 0.2=\dfrac{Given\:mass}{76}[/tex]
[tex]\\ \sf\longmapsto Given\:Mass=0.2\times 76[/tex]
[tex]\\ \sf\longmapsto Given\:Mass=1.52g[/tex]
number is equal to 6022 x 10^23
Answer:
The Avogadro's number
Explanation:
the number is 6.02214x10 to the 23 power
Which of the following is NOT a requirement for combustion to occur?
A. Fuel
B. Hydrogen
C. Heat
D. Oxygen
B ) Hydrogen
as O2 helps in combustion and Fuel is the one which is going to combust and heat is required to bring fuel to the combustion temperature
Which of the following is NOT a requirement for combustion to occur?
A. Fuel
B. Hydrogen
C. Heat
D. Oxygen
Answer:-[tex] \bold \pink{hydrogen}[/tex]
The four elements are oxygen for sustaining combustion, enough heat for raising the material to the ignition temperature, combustible material or fuel, and a subsequent exothermic chain reaction in the material.
The density of toluene (C7H8) is 0.867 and that of thiophene (C4H4S) is 1.065 g/ml. A solution is made by dissolving 10.00g thiophene in 250.00ml of toluene. a)Calculate the molarity of the solution
b)Assuming the volume are addictive ,calculate the molarity of the solution
Answer:
Calcular la molaridad de una solución que se preparó disolviendo 14 g de KOH en suficiente
agua para obtener 250 mL de solución. (masa molar del KOH = 56 g/mol).
Resolución: de acuerdo a la definición de “molaridad” debemos calcular primero, el número de mol de soluto (KOH) que
se han disuelto en el volumen dado, es decir, “se transforma g de soluto a mol de soluto” por medio de la masa molar,
así:
56 g de KOH 14 g de KOH
----------------- = ------------------- X = 0,25 mol de KOH
1 mol X
Ahora, de acuerdo con la definición de molaridad, el número de mol debe estar contenido en 1000 mL (o 1 L) de
solución, que es el volumen estándar para esta unidad de concentración, lo que se determina con el siguiente planteamiento:
0,25 mol X
----------------------- = ------------------------- X = 1 mol de KOH
250 mL de solución 1000 mL de solución
Explanation:
