Which general equation represents an endothermic reaction?
A. reactants - energy - products + energy
B. reactants
products + energy
C. reactants + products - energy
D. reactants + energy
products
Explanation:
The general equation for an endothermic reaction is: Reactants + Energy → Products.
Hope it helps :)❤
The equation represents an endothermic reaction is reactants + energy
products.
What is an endothermic reaction?
Endothermic reactions are chemical reactions in which the reactants soak up warm strength from the surroundings to form products.
net energy is not released.heat is not evolved with the product.heat is required to start the reaction.increase with the increase in temperature.decrease with a decrease in temperature.Learn more about the endothermic reaction here:-https://brainly.com/question/6506846
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The answer for this
1,3,5,7-Cyclooctatetraene, C8H8, is an unusual hydrocarbon in that it reacts with exactly 2 equivalents of potassium to give A, C8H8K2, which can be isolated as a white solid. A exhibits a single proton NMR signal. Draw the structure of A
Answer:
Explanation:
The main assignment here is to provide the structure of A. But before that, let us explain briefly some certain things:
The proton NMR (1H) gives data about the quantity of non-identical protons present in the structure. The resonance frequency is seen regarding the standard compound (0 ppm), which is addressed as a chemical shift. The same protons have equal value of chemical shift.
The protons that are available in a similar environment are addressed as comparable protons and the protons with various conditions are called non-identical protons.
However, from the image below, we can see the reaction of the compound 1,3,5,7-cyclooctatetraene resulting in 2 equivalents of potassium forming an aromatic dianion.
1. Calculate the percent composition of the elements in C4H8O2.
Answer:
%C = 54.53%
%H = 9.144%
%O = 36.32%
Explanation:
Step 1: Calculate the mass of each element in 1 mole of C₄H₈O₂
We will multiply the number of atoms by the molar mass of the element.
mC: 4 × 12.01 g = 48.04 g
mH: 8 × 1.007 g = 8.056 g
MO: 2 × 16.00 g = 32.00 g
Step 2: Calculate the mass of 1 mole of C₄H₈O₂
We will sum the previously calculated masses of the elements.
mC₄H₈O₂ = mC + mH + mO = 48.04 g + 8.056 g + 32.00 g = 88.10 g
Step 3: Calculate the percent composition of each element
We will use the following expression.
%Element = mElement / mCompound × 100%
%C = 48.04 g / 88.10 g × 100% = 54.53%
%H = 8.056 g / 88.10 g × 100% = 9.144%
%O = 32.00 g / 88.10 g × 100% = 36.32%
2.0M Propionic Acid HC3H5O2 Dissolves In Distilled Water. If It Has A Ka Of 1.3*10-5, What Is The Final PH?
The base ethylamine C2H5NH2 has a Kb of 5.6*10-4. What will the pH be in .53 molar solution?
Answer: first you have to calculate the amount ionized. We will say it is x mol / L
then % ionization = (amount ionized / initial concentration) * 100%
x can be calculated using an ice chart
HC3H5O2 -----> H+ + C3H5O2-
Initial HC3H5O2 = 0.250
change = -x
equilibrium = 0.250 - x
initial H+ = 0
change = +x
equilibrium = x
C3H5O2- initial = 0
change = +x
equilibrium = x
Ka = [H=][C3H5O2-] / HC3H5O2]
1.3 * 10 ^ -5 = [x][x] / (0.250 - x)
So 1.3 * 10 ^ -5 * (0.250 - x) = x ^ 2
3.25 * 10^ -6 - (1.3 * 10^-5)x = x^2 now this is a quadratic equation and you have to rearrange it and solve for x
x^2 + 1.3 * 10^-5)x - 3.25 * 10^ -6 = 0
use the equation x = {-b (+ or -)[b^2 - 4.a.c] ^ 1/2} / 2a
you should get x = 1.80 * 10 ^ -3 or x = -1.80* 10^-3
but x can not be negative..
so x = 1.80 * 10 ^ -3
so percent ionization = (1.80 * 10 ^ -3 / 0.250) * 100%
=0.72 %
the other way which is more easier is
assuming that x is very small and therefore 0.250 - x is approximately equals to 0.250
then 1.3 * 10^-5 = x^2 / 0.250
so x^2 = 1.3 * 10^-5 * 0.250
x = 1.80 * 10 ^-3
then percent ionization is = (1.80 * 10 ^ -3 / 0.250) * 100%
=0.72 %
if the percent ionization is > 5 % you can not do that approximation. in such a case you have to solve the quadratic equation. that is why I showed both methods.
now you can do the parts b and c
b answer : percent ionization = 1.27 %
c answer : 2.54%
good luck
- Explain why the term greenhouse effect is used to describe the theory of global
warming.
Does the greenhouse effect affect life on Earth? If yes, explain how?
What are the possible effects of a buildup of greenhouse gases in our atmosphere?
Which compound is more soluble in water at 25°C?
A.
MgF2 (Ksp = 5.2 x 10-11)
B.
SrF2 (Ksp = 7.9 x 10-10)
C.
AgBr (Ksp = 5.0 x 10-13)
D.
Agl (Ksp = 1.5 * 10-16)
Answer:
B
Explanation:
The solubility depends on the ksp. As the value of ksp increases the compound becomes more and more soluble.
In the options, the highest ksp value is 10^-10, thus that one is the most soluble.
Use the following balanced reaction to solve 1-3:
P4 (s) + 6H2 (g) → 4PH3 (g)
How many grams of phosphorus trihydride will be formed by reacting 60 L of Hydrogen gas with an excess of P4?
Answer:
60.86 g of PH₃
Explanation:
We'll begin by calculating the number of mole of H₂ that will occupy 60 L. This can be obtained as follow:
22.4 L = 1 mole of H₂
Therefore,
60 L = 60 / 22.4
60 L = 2.68 mole of H₂.
Next, we shall determine the number of mole of PH₃ produced by the reaction of 60 L (i.e 2.68 mole) of H₂. This can be obtained as follow:
P₄ + 6H₂ –> 4PH₃
From the balanced equation above,
6 moles of H₂ reacted to produce 4 moles of PH₃.
Therefore, 2.68 moles of H₂ will react to to produce = (2.68 × 4)/6 = 1.79 moles of PH₃.
Finally, we shall determine the mass of 1.79 moles of PH₃. This can be obtained as follow:
Mole of PH₃ = 1.79 moles
Molar mass of PH₃ = 31 + (3×1)
= 31 + 3 = 34 g/mol
Mass of PH₃ =?
Mass = mole × molar mass
Mass of PH₃ = 1.79 × 34
Mass of PH₃ = 60.86 g
Thus, 60.86 g of PH₃ were obtained from the reaction.
A solution has a [OH-] of 1.43x10-9. What is the pH of this solution?
a. 5.2
b. 8.8
C. 9.1
d. 4.9
Answer:
a. 5.2
Explanation:
pOH = -log(1.43 x 10^-9) = 8.845
pH = 14 - pOH = 14 - 8.845 = 5.155 ≈ 5.2
The heat of a reaction may be found with the equation q=mc triangle T. A 951 g sample of carbon steel with a specific heat capacity of 0.49 J/(g*K) is heated to 673K and quenched in oil. The steel cools to 523K. Assuming there is no heat lost to the surroundings, calculate the heat absorbed by the oil. A) -69.9kj B) -31.5kj C) 69.9 kJ D) 71.2 kj
Answer:b
Explanation:
Answer:
C.
Explanation:
I took the quiz and made a 100
formation of SO3 from SO2 and O2 is favoured by
a) increase in pressure
b) decrease in pressure
c) Increase in temperature
d)decrease in temperature
Answer:
answer is A. increase in pressure
l think this correct answer
The cell wall regulates what enters and exits the cell? True or False
Answer:
True
Explanation:
Answer:No, the Cell Membrane does I'm pretty sure
Explanation:
A certain metal M forms a soluble nitrate salt M(NO3), Suppose the left half cell ofa galvanic cell apparatus is filled with a 4.00 M solution of M (NO,), and the right half cell with a 20.0 mM solution of the same substance. Electrodes made of M are dipped into both solutions and a voltmeter is connected between them. The temperature of the apparatus is held constant at 35.0 °C.
Required:
a. Which electrode will be positive?
b. What voltage will the voltmeter show?
Answer:
Explanation:
The left electrode will be positive on the grounds that focus on the concentration that the cell electron moves from a lower concentration fixation to a higher concentration. Thus right electrode will go about and act as an anode and will be negative. Also, the left electrode will be the cathode and will be positive.
The concentration cell [tex]E_{Cell} = \dfrac{-0.0591}{1} log \dfrac{0.02}{4}[/tex]
[tex]E_{Cell} =0.136 V[/tex]
= 136 mV
what career field/job would utilize ppm units
A environmental jobs
B Medical fields
C Jobs at the brewery
D Jobs in analytical chemistry
Simone is helping her mom cook. She takes a glass casserole dish directly from the refrigerator and put it in the oven. Which best explains the result of putting the cold dish in the hot oven?
Group of answer choices
The dish stays cool and will not warm.
The dish quickly changes color.
The dish cracks or breaks.
The dish contracts and shrinks.
Answer:
I think the dish contracts and shrinks
Answer:
The dish cracks or breaks.
Explanation:
When glass changes temperature rapidly, it may undergo thermal shock. This is stress that is produced by a sudden change in temperature.
How many moles is equal 82.4 grams of CO,?
Answer:
1 mole = 28.0101
Hence,
82.4 = around 2.8 mole
Have a great day <3
Calculate the molarity of a solution that contains 3.00x10-2 mol NH4Cl in exactly 450 cm3 of solution.
Answer:
0.06moles/litres
Explanation:
molarity = no of moles / volume in litres = 3.00*10^-2/(450/1000)=0.06 moles/litres
Answer:
0.07mol/dm^3
Explanation:
Please mark as brainliest
Balance Chemical Equations, will give brainiest.
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1) 2KCIO3=2kci+3o2
2)CH4 + 2O2 → CO2 + 2H2O
3) 2HCl + Ca(OH)2 → CaCl2 + 2H2O
I hope this helped!
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2C2H2 + 502 = 4CO2 + 2H20
when 20000g of 2C2H2 + 5O2 = how much 4CO2?
Answer:
6.761 × 10⁴ g
Explanation:
Step 1: Write the balanced combustion reaction
2 C₂H₂ + 5 O₂ ⇒ 4 CO₂ + 2 H₂O
Step 2: Calculate the moles corresponding to 20000 g of C₂H₂
The molar mass of C₂H₂ is 26.038 g/mol.
20000 g × 1 mol/26.038 g = 768.11 mol
Step 3: Calculate the moles of CO₂ produced from 768.11 moles of C₂H₂
The molar ratio of C₂H₂ to CO₂ is 2:4.
768.11 mol C₂H₂ × 4 mol CO₂/2 mol C₂H₂ = 1536.2 mol CO₂
Step 4: Calculate the mass corresponding to 1536.2 moles of CO₂
The molar mass of CO₂ is 44.01 g/mol.
1536.2 mol × 44.01 g/mol = 6.761 × 10⁴ g
What is the total number of nitrogen atoms in two mol of NH4NO3?
Answer:
the answer is B if one mol contains of NH4NO3 contains 6.02X 10^23
what does pen mean?.
Answer:
P = protons
E = electrons
N = neutrons
remember protons and neutrons (protons are positive and neutrons are neutral as you can already tell by their names) are found at the centre of the nucleus (positive mass). Whilst the electrons (negative) orbit around the shells
What is the atomic mass of hafnium if, out of every 100 atoms, 5 have a mass of 176, 19 have a mass of 177, 27 have a mass of 178, 14 have a mass of 179, and 35 have a mass of 180.0? Answer with 2 decimals
Answer:
178.36 a.m.u
Explanation:
5 have a mass of 176,
5/100 * 176 = 8.8
19 have a mass of 177
19 / 100 * 176 = 33.44
27 have a mass of 178
27 / 100 * 178 = 48.06
14 have a mass of 179
14 / 100 * 179 = 25.06
35 have a mass of 180.0
35 / 100 * 180 = 63
Atomic Mass = 8.8 + 33.44 + 48.06 + 25.06 + 63
Atomic Mass = 178.36 a.m.u
when forces act in equal and opposite directions the net force is and the object
Answer:
Equal forces acting in opposite directions are called balanced forces. Balanced forces acting on an object will not change the object's motion. When you add equal forces in opposite direction, the net force is zero.
Explanation:
If 3 moles of NaOH is dissolved in 4L of water, what is the
molarity of the solution?
Answer:
0.75mol/LNaOH
Explanation:
Data: Soln:
M= ? M= n/ V(l)
n= 3moles. M= 3mol/ 4L
V= 4L. M = 0.75 mol/LNaOH
Which is a similarity between a fish embryo and a bird embryo in the early stages of development?
Gill slits
forelimbs
jaw bones
hindlimbs
Answer:
Gill Slits
Explanation:
For the one who asked what hind limbs are they are back legs :)
Na + H2O = NaOH
Balance the following equation
Answer:
Na+H2O =NaO+ H2
Explanation:
Because nitrogen is one , so it is balanced. And Oxygen is one,it is balanced. And Hydrogen is 2 ,and hence it is also balanced.
Rank the following compounds in order of decreasing acidity. Be sure to answer all parts. A) Benzyl alcohol B) Methylbenzene C) Benzoic acid
The order of decreasing the acidity of the given compounds:
Benzoic acid > Benzyl alcohol > Methylbenzene.
What is the acidic strength?The acidic strength of an acid can be described as the ability of the acid to lose its H⁺ ion. In general, the dissociation of acid can be represented as:
HA → H⁺ + A⁻
Some examples of strong acids are hydrochloric acid, sulfuric acid (H2SO₄), perchloric acid (HClO₄), etc.
The benzoic acid is a very strong acid with pka value of 4.5 as it contains the (-COOH) group. The Benzyl alcohol with pka value of 15.4 as it contains the (-CH₂OH) group attached to the benzene ring. The methylbenzene with pka value of 41 has the lowest acidity as it contains the methyl group attached to the benzene ring.
Therefore, the order of acidic strength for the given compounds is Benzoic acid > Benzyl alcohol > Methylbenzene.
Learn more about acidic strength, here:
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The action of a tree stump splitting bedrock depicts what type of process?
А. chemical weathering
B. physical weathering
С. deposition
D. erosion
Answer: Physical Weathering
Explanation: It is physical weathering because it is caused by natural elements causing the rock to break. It is not chemical weathering because it is not using any chemical reaction to break the rock. It is not erosion or deposition because it is still not finished with the process with breaking the rock. Think of it this way:
Step 1: Weathering - Breaks rock/stone
Step 2: Erosion - Taking the small bits of rock
Step 3: Deposition - Dropping the rock
What do scientists mean when they refer to population
population is the number of species living in a given area if this is regarding biology or earth studies :)
Advise a friend who responds to conflict by using the strategies below on why
each (strategy) is not healthy for sustaining positive relationships.
a. Confrontation
Answer:
When there is a conflict and if a friend responding to conflict with confrontation it may affect positively or negatively both ways depend how he responds or confront the other person he has a conflict with. But normally people alienate with the person being confrontational. A friend should try to resolve the conflict by making an amicable solution.
if it is used correctly it could help in making the relationship strong, however, confronting by attacking them verbally, insult them, or talking loudly among the group of people can escalate the conflict.
I will advise him to be cautious of the approach as it may positively or negatively affect the situation.
What is Confrontation?This is the process which involves directly engaging one another in the course of a dispute between them.
This method however could either resolve the conflict or worsen it which is why special approach should be taken by being calm and being respectful to the other party involved.
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