Answer:
Combustion as an Exothermic Reaction
Explanation:
When substances burn, they usually give off energy as heat and light. The combustion of wood is an exothermic reaction that releases a lot of energy as heat and light.
Answer:
Exothermic
Explanation:
because exothermic causes fires while endothermic doesn't
Describe the kinds of potential energy that are stored by a car driving on a hill.
Answer:
The internal combustion engine in the car converts the potential chemical energy in gasoline and oxygen into thermal energy which is transformed into the mechanical energy that accelerates the vehicle (increasing its kinetic energy) by causing the pressure and performing the work on the pistons.
Explanation:
Define Evaporation.
Thanks
Answer:
evapouration is a type of vaporization that occur on the surface of liquid as it change into the gas phase.
hope it helps.
Evaporation happens when a liquid turns into a gas. It can be easily visualized when rain puddles “disappear” on a hot day or when wet clothes dry in the sun.
Which statement is true about the particles of a liquid when the liquid changes into a solid?
They move closer to each other.
Their kinetic energy increases.
They stop vibrating.
The attractive force between them decreases.
Answer:
they move closer to each other
Answer:
They move closer to each other
Explanation:
Got it right on the test
Hope this helps :)
gas
LA of certain mass occupies a volume of 650 cm3 under
a pressure of 760mmHg. Calculate the pressure under which
the volume of the
gas
cent
of its original volume
will be reduced by 10 per
Answer:
844.4cm³
Explanation:
Using Boyle's law equation;
P1V1 = P2V2
Where;
P1 = initial pressure (mmHg)
P2 = final pressure (mmHg)
V1 = initial volume (cm³)
V2 = final volume (cm³)
According to the information in this question,
V1 = 650cm³
P1 = 760mmHg
P2 = ?
V2 = 10% reduction of V1
10% of 650 = 10/100 × 650
65
V2 = 650 - 65 = 585cm³
Using P1V1 = P2V2
P2 = P1V1 ÷ V2
P2 = (760 × 650) ÷ 585
P2 = 494000 ÷ 585
P2 = 844.44
final pressure (P2) = 844.4cm³
The temperature of 335 g of water changed from 24.5oC to 26.4oC. How much heat did this sample absorb? C for water = 4.18 J/goC
Answer: The sample absorbed 3061.565J
Explanation:
Given that
Mass of water = 335g
Initial temperature = 24.5°C
Final temperature = 26.4°C
Heat absorbed by the sample is given as = mass x specific heat of water x temperature change
Heat absorbed,q=mCΔt
The specific heat of water,C = 4.81J/g°C
Therefore, Heat absorbed,q = 335 x 4.81h x (26.4 - 24.5) = 3061.565J
Answer:
2660.57 J
Explanation:
26.4 - 24.5 = 1.9
335 x 4.18 x 1.9 = 2660.57 J
That is the correct answer.
An electric car has a mass of 2,000 kg. the engine is producing a force of 3,500 N to move the vehicle forward,but it must overcome air friction equal to 500 N
What is the acceleration of the electric car m/s2?
record your answer and fill in below
Answer:
1.5 m/s²
Explanation:
From the diagram,
F-F' = ma............... Equation 1
Where F = Forward force of the vehicle, F' = Frictional force, m = mass of the electric car, a = acceleration of the car.
make a the subject of the equation
a = (F-F')/m........... Equation2
Given: F = 3500 N, F' = 500 N, m = 2000 kg
Substitute into equation 2
a = (3500-500)/2000
a = 3000/2000
a = 1.5 m/s²
explain in 3 complete sentences
Answer:Air in high pressure systems moves in an anticlockwise direction (in the southern hemisphere), while air in low pressure systems moves in a clockwise direction due to the rotation of the Earth. At the surface of the Earth air flows from high pressure systems into low pressure systems.
Explanation:
Warm air rises, creating a low pressure zone; cool air sinks, creating a high pressure zone. Air that moves horizontally between high and low pressure zones makes wind.Smaller pressure systems create localized winds that affect the weather and climate of a local area.
A helium balloon with a volume of 5.0 L and a pressure of 105 kPa at 25°C floats up high in the sky where the pressure is 850 mm Hg and the temperature is -15°C. What is the new volume of the balloon?
Answer:
volume 2- 4.011 L
2 H2 (g) + O2 (g) --> 2 H2O (l)
How many moles of hydrogen gas do you need to make 2 moles of liquid water?
Answer:
2H2(g]+O2(g]→2H2O(l]]. Notice that the reaction requires 2 moles of hydrogen gas and 1
Explanation:
For a reaction which change can increase the rates of reaction?
Answer:
temperature!!!
Explanation:
Reactant concentration, the physical state of the reactants, and surface area, temperature, and the presence of a catalyst are the four main factors that affect reaction rate.
How many grams of NaOH are produced from 2.1g of Na2O?
Na2O + H20 --> 2NaOH
Answer:
2.72g
Explanation:
The balanced equation of this reaction is given as follows:
Na2O + H20 --> 2NaOH
Based on this balanced equation, 1 mole of Na2O will produce 2 moles of NaOH.
First, we need to convert mass of Na2O into moles by using the formula;
mole = mass/molar mass
Molar mass of Na2O = 23(2) + 16
= 46 + 16
= 62g/mol
mole = 2.1g/62g/mol
mole of Na2O = 0.034mol
Hence, if 1 mole of Na2O will produce 2 moles of NaOH.
Then, 0.034mol of Na2O will produce (0.034 × 2) = 0.068mol of NaOH.
To convert mole of NaOH to mass, we use;
mole = mass/molar mass
Molar mass of NaOH = 23 + 16 + 1 = 40g/mol
0.068 = mass/40
mass of NaOH produced = 2.72g.
How is evaporation related to molarity?
Answer:
Molarity is the amount (in mole) of solute in a solvent. If the solute is very volatile, then it will evaporated from the solution as temperature rising. So the amount of solute is decreasing, causing the molarity decreasing. If the solvent itself volatile, then the molarity will increase.
(Looked up the answer for you)
The relationship between evaporation and molarity is; the rate of evaporation of will decrease as the molarity increases
What is evaporation and molarity?
Molarity (M) is defined as the amount of a substance in a certain volume of solution. Molarity can also be defined as the number of moles of a solute per liters of a solution.
Now, the rate of evaporation of will decrease as the solute concentration increases due to the fact that for the same surface area for evaporation, as the concentration of the solute increases, less water molecules will get exposed to escape from the water surface.
Read more about Evaporation and Molarity at; https://brainly.com/question/14718840
When a mixture of iron powder and sulphur is heated it glows more brightly than that of iron filings and sulphur.Explain this observation
Answer:
I don't know
Explanation:
mixture of iron powder and sulphur heated it glows because sulphur and iron are more reactive metals that they shine and sulphur can react with water produce fire it's write
5 Which two elements are combined in magnesium oxide?
Answer:
magnesium and oxygen
Explanation:
4Fe+3O2 →2Fe2O3
80.0 grams of iron are reacted with 50.0 grams of oxygen gas. Which of these reactants are the limiting reactant, and how many grams of iron (III) oxide would be produced?
Answer:
FFe
2
O
3
(
s
)
+
3
CO
(
g
)
→
2
Fe
(
s
)
+
3
CO
2
(
g
Explanation:
If you can solve these thank you I will mark brainly.ASAP
Answer:Number 2 might be the second one
Explanation:
The shoes are green, a size 8, have white laces, made out of cotton, and have a rubber sole. The description given is a list of ___________ properities of the shoes. Question 33 options:
chemical
mechanical
physical
structural
Answer:
Physical i think, because it says, "The shoes are green, made of cotton, and rubber sole" everything in the passage described a physical property
Explanation:
tell me if im wrong, good luck
Answer:
physical
Explanation:
its listing a size 8, which eliminates chemical and mechanical. Also it lists their green, which eliminates structural, leaving physical left
Does anyone know the simplest way to find the rate constant in rate law chemistry?
Answer:no I don’t sorry
Explanation:
Question of the day
Seeds obtain their energy (food) directly from the soil as soon as they are planted.
True or False?
Answer:
false
Explanation:
it gets nourishment from the storage tissues in the seeds, when it develops into a young plant with roots, then it takes nutrients from the soil
What type of ionic compound is CO3?
Answer:
Carbon Trioxide
Explanation:
Its a Carbonite Ion which is also known as a polyatomic ion
How many moles are in 3.4*10²⁶ molecules of H2O?
Answer:
564.5027395 moles
Explanation.
a mole is 6.023×1023
(3.4×10^26)÷(6.023×10^23)= 564.5027395
A gas system has an initial number of moles of 0.693 moles with the volume unknown. When the number of moles changes to 0.928 moles volume is found to be 7.98 L. What was the initial volume in mL?
Answer:
The initial volume in mL is 5959.2 mL
Explanation:
As the number of moles of a gas increases, the volume also increases. Hence, number of moles and volumes are directly proportional i.e
n ∝ V
Where n is the number of moles and V is the volume
Then, n = cV
c is the proportionality constant
∴n/V = c
Hence n₁/V₁ = n₂/V₂
Where n₁ is the initial number of moles
V₁ is the initial volume
n₂ is the final number of moles
and V₂ is the final volume.
From the question,
n₁ = 0.693 moles
V₁ = ?
n₂ = 0.928 moles
V₂ = 7.98 L
Putting the values into the equation
n₁/V₁ = n₂/V₂
0.693 / V₁ = 0.928 / 7.98
Cross multiply
∴ 0.928V₁ = 0.693 × 7.98
0.928V₁ = 5.53014
V₁ = 5.53014/0.928
V₁ = 5.9592 L
To convert to mL, multiply by 1000
∴ V₁ = 5.9592 × 1000 mL
V₁ = 5959.2 mL
Hence, the initial volume in mL is 5959.2 mL
Un convertidor catalítico acelera la reacción del monóxido de carbono con oxígeno para producir dióxido de carbono. ¿De qué manera cada uno de los siguientes cambios afectaría la velocidad de reacción que se muestra aquí? Sustente 2CO (g) + O2(g) → 2CO2(g) a). Quitar el catalizador. B). Eliminar parte de O2(g)
Answer:
a. Disminuye.
b. Disminuye.
Explanation:
¡Hola!
En este caso, considerando que tenemos una reacción en la cual se podría asumir que tanto la concentración de monóxido de carbono y la de oxígeno contribuye a la velocidad de reacción, de acuerdo a la siguiente cinética elemental:
[tex]r=k[CO]^2[O_2][/tex]
Al aplicar los siguientes cambios, resultaría:
a. En este caso, bien sabemos que la velocidad de reacción es aumentada al adicionar un catalizador ya que la constante de velocidad aumenta al disminuir la energía de activación; no obstante, al retirar el catalizador, la energía de activación aumentaría y por consiguiente la velocidad de reacción disminuiría.
b. En este caso, dado que la relación entre el oxígeno y la rapidez de reacción es directamente proporcional, es possible para nosotros determinar que al eliminar parte del oxígeno, la concentración disminuye y por ende la velocidad de reacción también.
¡Saludos!
Now that you have exercised, walked your
jackalope, made cookies, and had juice, you
decide on a nap. Your body uses melatonin to
tell your brain and body that it's ready to sleep
or nap. Melatonin has the chemical formula
C13H16N2O2. The amount in your body at any
time is very small - less than 10 milligrams
(0.01 g)! Convert the melatonin to moles so
you can rest
Answer: The moles of melatonin are 0.000043
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
Given mass of melatonin = 0.01 g
Molar mass of melatonin [tex](C_{13}H_{16}N_2O_2)[/tex] = 232.28 g/mol
[tex]\text{Number of moles of melatonin}=\frac{0.01 g}{232.28g/mol}=0.000043mol[/tex]
Thus the moles of melatonin in 0.01 g are 0.000043
Texas hill country is largely composed of soft limestone rock. When exposed to carbonic acid in rainwater, limestone can deteriorate and weaken. What affect does this process have on the landforms of Texas hill country?
Answer:
The answer is "It leads to the formation of underground caves"
Explanation:
Texas Hill Land is popular for its rolling hills, good wine, and authentic food. Its Texas Hill Property appeal is no mystery, recognized as being one of the top vacation destinations in the World. Texas Hill Structure is primarily mostly of weak calcareous stone. Calcium may worsen or degrade if exposed to carbon dioxide in rainwater. This practice affects the land of the Texas smoky Mountains leading to the formation of underwater groves.
How many moles are in 564 grams of copper
Answer:The answer is 63.546.
Explanation: The answer is 63.546. We assume you are converting between grams Copper and mole. You can view more details on each measurement unit: molecular weight of Copper or mol. The molecular formula for Copper is Cu. The SI base unit for amount of substance is the mole. 1 grams Copper is equal to 0.015736631731344 mole
Answer:
5.64 of copper
Explanation:
Given: 564 grams of copper
To find: in copper
Solution: If 1 grams Copper = 0.01 mole,
Then, 564 grams = multiply 564 and 0.01 mole
564 × 0.01 = 5.64
Therefore, there are 5.64 of copper in 564 grams
When hydrogen peroxide (H2O2) is used in rocket fuel, it produces water and oxygen (O2): Can someone help with parts B and C?
Answer:
Explanation: A foam forms when bubbles of a gas are trapped in a liquid or solid. In this case oxygen is generated when hydrogen peroxide breaks down into oxygen and water on contact with catalase, an enzyme found in liver. Enzymes are special protein molecules that speed up chemical reactions.
A photon of visible light can be emitted when
Select one:
O a. an excited electron jumps down to ground state
O b. a ground state electron absorbs energy
O c. a ground state electron jumps to a higher energy level
Answer:
a ground state electron jumps to a higher energy level
A box slides with an initial speed of 4.0 towards a spring on a frictionless horizontal surface. When the box
S
N
hits a spring with spring constant k = 150 the spring compresses by 0.30 m.
m
m
M
What is the mass of the box?
Answer: .84kg
Explanation:
Khan academy
A box slides with an initial speed of 4.0 kg m/s towards a spring on a frictionless horizontal surface. When the box hits a spring with spring constant k = 150 N/m, the spring compresses by 0.30 m.
What is the mass of the box?
Answer: 0.54 kg
Which on is right O& Mg?
OMG
MgO
Mg2O2
Mg+2O-2
Answer:
MgO
is the correct answer
hope it helps