Answer:
5 grams remain
Explanation:
A = A₀exp(-k·t) 80g·exp(-0.00238yr⁻¹)(1165yrs) = 80g x 0.063 = 5 grams remain
a solution is prepared by dissolving 4.85 g of HCl into enough water to make 2.50 L of a solution
Answer:
0.0532 M
Explanation:
Just did the test :)
Carbon dioxide and water react to form methanol and oxygen, like this:
2CO2(g) + 4H2O(g) → 2CH3OH(l) + 3O2 (g)
At a certain temperature, a chemist finds that a 7.5L reaction vessel containing a mixture of carbon dioxide, water, methanol, and oxygen at equilibrium has the following composition:
Compound Amount
CO2 3.28g
H2O 3.86g
CH3OH 1.51g
O2 2.80g
Required:
Calculate the value of the equilibrium constant Kc for this reaction. Round your answer to 2 significant digits.
Answer:
24x10³
Explanation:
2CO₂(g) + 4H₂O(g) → 2CH₃OH(l) + 3O₂ (g)
The equilibrium constant for this reaction is:
Kc = [tex]\frac{[O_2]^3}{[CO_2]^2[H_2O]^4}[/tex]
The expression of [CH₃OH] is left out as it is a pure liquid.
Now we convert the given masses of the relevant species into moles, using their respective molar masses:
CO₂ ⇒ 3.28 g ÷ 44 g/mol = 0.0745 mol CO₂H₂O ⇒ 3.86 g ÷ 18 g/mol = 0.214 mol H₂OO₂ ⇒ 2.80 g ÷ 32 g/mol = 0.0875 mol O₂Then we calculate the concentrations:
[CO₂] = 0.0745 mol / 7.5 L = 0.0099 M[H₂O] = 0.214 mol / 7.5 L = 0.0285 M[O₂] = 0.0875 mol / 7.5 L = 0.0117 MFinally we calculate Kc:
Kc = [tex]\frac{0.0117^3}{0.0099^2*0.0285^4}[/tex] = 24x10³What does pcv means in medical terms
Answer:
packed-cell volume
Explanation:
The order of the layers from the inside of the Earth outwards is:
(10 Points)
Mantle, crust, core
Core, mantle, crust
Core, crust, mantle
Mantle, core, crust
Rank the following compounds in order of decreasing acid strength using periodic trends. Rank the acids from strongest to weakest.
a. HCl
b. H2S
c. HBr
d. BH3
Answer:
HBr > HCl > H2S > BH3
Explanation:
In many acids, the magnitude of electronegativity of the nonmetal determines the strength of the acid. The less electronegative the non-metal is, the stronger the acidity of the acid.
This is because the less electronegative the nonmetal is, the more easily the H-X bond is broken since it is longer and weaker.
This explains the order of acid strength shown in the answer above.
Respiration takes place in:
O only plants
O only animals
O both plants and animals
Answer:
both
Explanation:
plants have mitochondria and can preform cellular respiration
animals and plants use oxygen in respiration to produce corbon dioxide
Answer:
I think it's both.
Explanation:
I just looked it up, so yeah.
what volume of nitrogen gas is equal too 3.42x10^22 molecules of this substance
if i am correct the volume of nitrogen gas has to equal to molecules density, making the substance 1.27 liters :)
PLS HELP!! 40 POINTS (Absurd or Spam answers will be reported. No copying from other answers.)
Phases of Matter Activity
Now it is your turn to show what you know about phases of matter and thermal energy transfer! Your task is to create a presentation to explain the transformation of a substance as it changes phases. You may choose to write a story or create a comic strip. For your story or comic, you will create a main character and detail the adventure as your character is exposed to thermal energy, causing it to undergo phase changes from a solid, to a liquid, to a gas. You may create your own comic strip using drawings, presentation software, or this comic strip template.
Your presentation must include the following:
title and introduction of your character, including what substance the character is made of
source of thermal energy your character encountered (conduction, convection, and/or radiation)
detailed description and/or diagram of the particle transformation from solid to liquid phase
detailed description and/or diagram of the particle transformation from liquid to gas phase
You may get creative on this activity. If you are unsure if your idea or software for a presentation will work, contact your instructor for assistance. Be sure to review the grading rubric before you begin.
Answer:
lol i know this isnt the best but Your comic strip can be about how when you put smores in a campfire, the smores become burnt that is example of energy transfer because energy is traveling as heat to another object.
Explanation:
Calculate the number of moles of solute in 27.55 mL of 0.1185 M K2Cr2O7(aq).
Answer:
0.01185M = moles/0.02755L
0.02755*0.01185=0.00032647
Explanation:
How much heat must be added to heat 0.750 g of water from 20.0 degrees * C to 40.0C (Remember, Q=C*m* Delta T) The specific heat of water is joule/gram.
D. 62.8 J
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Thermodynamics
Specific Heat Formula: q = mcΔT
q is heat (in joules)m is mass (in grams)c is specific heat (in J/g °C or J/g K)ΔT is change in temperature, final minus initial (°C or K)Explanation:Step 1: Define
[Given] m = 0.750 g
[Given] c = 4.186 J/g °C
[Given] ΔT = 40.0 °C - 20.0 °C = 20.0 °C
[Solve] q
Step 2: Solve
Substitute in variables [Specific Heat Formula]: q = (0.750 g)(4.186 J/g °C)(20.0 °C)[Heat] Multiply [Cancel out units]: q = 62.79 JStep 3: Check
Follow sig fig rules and round. We are given 3 sig figs.
62.79 J ≈ 62.8 J
What is the reaction when you take hydrogen gas and oxygen gas to form liquid hydrogen peroxide
Answer:
Hydrogen gas (H2) and oxygen gas (O2) react to form liquid hydrogen peroxide (H2O2). The atoms of the reactants have combined to form a new substance. The new substance has its own set of properties that is different from the properties of each reactant.
Explanation:
what type of intermolecular interaction predominates in the following substances
Answer:
1. C
2. D
Explanation:
Some signs of chemical change include
(Select only 1 answer)
A)All of these
B)producing an odor
C)changing color
D)releasing gas
Answer:
I think it would be A honestly...
A. What is the pH of 8.9 × 10−3 M HCl?
B. What is the pH of 8 × 10−8 M HCl?
Answer:
A. p(H) = 2.0506
B. p(H) = 7.0969
Explanation:
A.
p(H)= -log[H+]
p(H)= -log(8.9×10^-3)
p(H) = 2.0506
B.
p(H)= -log[H+]
p(H)= -log(8×10^-8)
p(H) = 7.0969
List the Van't Hoff factor for each of the following solutes and rank their conductivities in solution. Whoever helps me first gets brainliest!!!
Ca(OH)2, SO2, LiCL
Answer:
hopefully this helps is not i have more just let me know
Explanation: #1 Identify the colligative property.
A) vapor pressure lowering
B) freezing point depression
C) boiling point elevation
D) osmotic pressure
E) all of the above
#2 ________ is applied to roads in wintertime so that the ice will melt at a lower temperature.
A) Antifreeze
B) Water
C) Salt
D) Sugar
E) Oil
#3 Give the reason that antifreeze is added to a car radiator.
A) The freezing point is lowered and the boiling point is elevated.
B) The freezing point is elevated and the boiling point is lowered.
C) The freezing point and the boiling point are elevated.
D) The freezing point and the boiling point are lowered.
E) None of the above.
4# Place the following aqueous solutions of nonvolatile, nonionic compounds in order of decreasing osmotic pressure.
I. 0.011 M sucrose
II. 0.00095 M galactose
III. 0.0060 M glycerin
A) I > III > II
B) I > II > III
C) II > III > I
D) III > I > II
E) II > I > III
5# Place the following solutions in order of increasing osmotic pressure. I. 0.15 M C2H6O2 II. 0.15 M BaCl2 III. 0.15 M NaI A) III < I < II B) II < III < I C) I < II < III D) II < I < III E) I < III < IIPLEASE HELP
CH4 + 2O2
Answer:
the answer of the question is =ch4+2o2
A substance has a specific heat capacity of 2.0 J/g °C. How many joules are needed to raise the temperature of 30.0 g of this substance from 0°C to15°C?
a. 1 J
b. -1 J
c. -900 J
d. 900 J
Answer:
g
Explanation:
know what you think about th can get it
Answer:
[tex]\Large \boxed{\sf 900 \ J}[/tex]
Explanation:
Use formula
[tex]\displaystyle \sf Energy\ (J)=mass \ (g) \times specific \ heat \ capacity \ (Jg^{-1}\°C^{-1}) \times change \ in \ temperature \ (\°C)[/tex]
Substitute the values in formula and evaluate
[tex]\displaystyle \sf Energy\ (J)=30.0\ g \times 2.0 \ Jg^{-1}\°C^{-1} \times (15\°C-0\°C)[/tex]
[tex]\displaystyle Q=30.0 \times 2.0 \times (15-0 )=900[/tex]
explain answer too, CHEM HELP
Which sentence correctly explains the process and conditions needed for rain to form?
A. Rain only falls during thunderstorms and extreme weather in below freezing temperatures.
B. Ice crystals melt as they fall through a layer of warm air and then refreeze into a solid form as they fall.
C. Water vapor freezes into solid ice crystals, and the temperature of the air should be below freezing.
D. The temperature in the sky needs to be above freezing, and water vapor condenses into liquid water.
Answer:
B. Ice crystals melt as they fall through a layer of warm air and then refreeze into a solid form as they fall.
Explanation:
Answer:B
Explanation:
All of these are examples of things that produce light energy except.
a. candle
b.flashlight
cDesklamp
d.compass
Answer:
Explanation:
A compass. Its main purpose is to tell what direction you are travelling.
In the equation:
2H2 + O2 --> 2H2O
What mass of Hydrogen Gas will completely react with 4 moles of Oxygen gas
(Hint: going from moles to mass of another compound)
A)8 g
B)16 g
C)24 g
Answer:
B) 16 g
Explanation:
2H₂ + O₂ → 2H₂OFirst we convert 4 moles of O₂ into moles of H₂, using the stoichiometric coefficients of the balanced reaction:
4 mol O₂ * [tex]\frac{2molH_2}{1molO_2}[/tex] = 8 mol H₂Finally we convert 8 moles of H₂ into grams, using its molar mass:
8 mol H₂ * 2 g/mol = 16 gThus, the correct answer is option B).
Which of the following is not part of the nucleus?
A. Ribosome
B. Chromosome
C. Nucleus
D. Gene
I believe the answer is Ribosome
_HNO3+ Fe+2
2+ H+ +_NO+ Fe+3+ H2O
What is the coefficient for water after the equation is balanced?
Answer: The coefficient for water after the equation is balanced is 2.
Explanation:
The balanced chemical equation must have same charge and same number of atoms on both sides of the equation.
As the given reaction is a redox recation occuring in acidic medium.
[tex]HNO_3+3Fe^{2+}+3H^+\rightarrow NO+3Fe^{3+}+2H_2O[/tex]
The coefficient for water will be 2 after the equation is balanced.
The difference between voltaic and electrolytic cells is that:
Answer:
Voltaic cells convert chemical energy to electrical energy by means of an oxidation-reduction reaction. Electrolytic cells convert electrical energy to chemical energy, so they are the opposite of voltaic cells. They require an input of electrical energy to cause an oxidation-reduction reaction.
Explanation:
that good enough for ya my asian friend?
Answer:
This is the answer hopefully you understand this also can you mark me brainliest pls
Can someone please help me
Answer:
Potassium iodide increases the decomposition rate of hydrogen peroxide.
Explanation:
Potassium iodide increases the decomposition rate of hydrogen peroxide because potassium iodide act as a catalyst. A catalyst speed up the process of chemical reaction without reacting with the molecules present in reaction. If the potassium iodide is not present as a catalyst for the decomposition of hydrogen peroxide then the decomposition of hydrogen peroxide takes too much time because the catalyst is absent that speed up the reaction.
1. An unknown amount of water
was heated with 3.5 kJ, raising
its temperature from 26°C to
66°C. What was the mass of
the water?
Answer:
20.93 g
Explanation:
From the question given above, the following data were obtained:
Heat (Q) = 3.5 KJ
Initial temperature (T₁) = 26°C
Final temperature (T₂) = 66°C
Mass (M) =?
Next, we shall convert 3.5 KJ to J. This can be obtained as follow:
1 KJ = 1000 J
Therefore,
3.5 KJ = 3.5 KJ × 1000 J / 1 KJ
3.5 KJ = 3500 J
Next, we shall determine the change in the temperature of the water. This is illustrated:
Initial temperature (T₁) = 26°C
Final temperature (T₂) = 66°C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 66 – 26
ΔT = 40 °C
Finally, we shall determine the mass of the water. This can be obtained as follow:
Heat (Q) = 3500 J
Change in temperature (ΔT) = 40 °C
Specific heat capacity (C) = 4.18 J/gºC
Mass (M) =?
Q = MCΔT
3500 = M × 4.18 × 40
3500 = M × 167.2
Divide both side by 167.2
M = 3500 / 167.2
M = 20.93 g
Therefore, the mass of the water is 20.93 g
Please help me thanks so much
Answer:
the answer is in the next one I just answered
Which layer of the ocean can support organisms that photosynthesize?
Answer:
Epipelagic zone
Explanation:
The Epipelagic zone is the upper most layer of the ocean. It is the layer which receives maximum sunlight, because of availability of sunlight and nutrients like fresh oxygen and atmospheric carbon dioxide, this zone is suitable for active photosynthesis activity.
___Cl2 + ___NaBr → ___NaCl + ___Br2 Which of the following coefficients will balance the chemical equation?
Answer:
2NaBr + Cl2 =2NaCl + Br2
Explanation:
Change the coefficient in from of the NaCl so you have the same number of Cl atoms on both sides.
Change the coefficient in front of the NaBr to balance the Br atoms as well as the Na.
Answer:
1,2,2,1
hope it helps
this is correct answer of this question
the sum of all potential and kinetic energies for all particles in the system is called what?
Answer:
mechanical energy
hope it helps and your day will be full of happiness