Answers
Answer:
B,C,D
Explanation:
Hope this helps.
Related Questions
How to we measure energy?
Answers
Answer:
The official measurement unit for energy is the Joule (J). Among the most common units measuring energy mention should be made of the kilowatt/hour (kWh), used especially for electric energy (in fact it is used to calculate electricity bills).
Question:
In a laboratory demonstration, a balloon filled with methane and oxygen was exposed to a
flame. The result was a brief, large flame. The students were asked to formulate an equation for
the reaction. One answer is below.
CH, + 0 = CO,
This equation is incorrect.
A. Explain how and why it is incorrect
B. What would the correct equation be, and how do you know that?
Answers
Answer:
The laboratory demonstration consists of the following;
The compounds present in the combustion reaction = Methane, CH₄ and Oxygen, O₂
The chemical equation for the combustion reaction is given as follows;
CH₄ + 2O₂ → CO₂ + 2H₂O
Therefore;
A. The equation given as CH₄ + O → CO₂ is not correct because;
1) Oxygen gas exist as diatomic molecules, O₂, and given that the experiment involves the mixture of gases, the oxygen gas present which can exist as a separate compound, should be represented as O₂
2) The number of oxygen molecules in the reaction is two rather than one
3) The product also includes two molecules of water (vapor) H₂O
B. The correct equation for the reaction should be given as follows;
CH₄ + 2O₂ → CO₂ + 2H₂O
B i) The constituents of the equation is obtained by the knowledge of the fact that the combustion reaction of an organic substance such as methane in the presence of oxygen yields, carbon dioxide and water (vapor)
The equation showing the relative amounts the reacting compounds is by balancing the basic equation of the combustion of methane in the presence of oxygen
Explanation:
Ethanol (C2H5OH) melts at –114 °C and boils at 78 °C. The enthalpy of fusion of ethanol is 5.02 kJ/mol, and its enthalpy of vaporization is 38.56 kJ/mol. The specific heats of solid and liquid ethanol are 0.97 J/g-K and 2.3 J/g-K, respectively. The average specific heat of gaseous ethanol is about 1.80 J/g-K. a. How much heat is required to convert 35.0 g of ethanol at 27 °C to the vapor phase at 120 °C? b. How much heat is required to convert the same amount of ethanol at –120 °C to the vapor phase at 120 °C?
Answers
Answer:
First question
[tex]Q = 36826 \ J[/tex]
Second question
[tex]Q = 52299.7 \ J[/tex]
Explanation:
From the question we are told that
The melting point of Ethanol is [tex]T_m = -114 ^oC[/tex]
The boiling point of Ethanol is [tex]T_b = 78^ oC[/tex]
The enthalpy of fusion of Ethanol is [tex]F = 5.02 \ kJ / mol = 5.02 *10^{3}\ kJ / mol[/tex]
The enthalpy of vaporization of Ethanol is [tex]L = 38.56 \ kJ / mol = 38.56 *10^{3} \ J / mol[/tex]
The specific heat of solid Ethanol is [tex]c_e = 0.97 \ J/ g \cdot K[/tex]
The specific heat of liquid Ethanol is [tex]c_l = 2.3 \ J / g \cdot K[/tex]
The mass of the Ethanol given is [tex]m = 35.0 \ g[/tex]
Considering the first question
The initial temperature is [tex]T_i = 27^oC[/tex]
The final temperature is [tex]T_f = 120^oC[/tex]
Generally the heat required too raise the Ethanol to its boiling point is mathematically represented as
[tex]Q_1 = m * c_l * (T_b - T_i)[/tex]
=> [tex]Q_1 = 35.0 * 2.3 * ( 78 - 27)[/tex]
=> [tex]Q_1 =4106 \ J[/tex]
Genially the number of moles of Ethanol given is mathematically represented as
[tex]n = \frac{m}{Z}[/tex]
Here Z is the molar mass of Ethanol with value [tex]Z = 46 g/mol[/tex]
So
[tex]n = \frac{35}{46 }[/tex]
=> [tex]n = 0.7609 \ mol[/tex]
Generally the heat of vaporization of the Ethanol is mathematically represented as
[tex]Q_2 = n * L[/tex]
=> [tex]Q_2 =0.7809 * 38.56 * 10^{3}[/tex]
=> [tex]Q_2 =29339 \ J[/tex]
Generally the heat required too raise the Ethanol from its boiling point to [tex]T_f[/tex] is mathematically represented as
[tex]Q_3 = m * c_l * (T_f - T_b)[/tex]
=> [tex]Q_3 = 35 * 2.3 * (120 - 78 )[/tex]
=> [tex]Q_3 = 3381 \ J[/tex]
Generally the total heat required is
[tex]Q = Q_1 + Q_2 + Q_3[/tex]
=> [tex]Q = 4106 + 29339 + 3381[/tex]
=> [tex]Q = 36826 \ J[/tex]
Considering the second question
The initial temperature is [tex]T_i = -120^oC[/tex]
The final temperature is [tex]T_f = 120^oC[/tex]
Generally the heat required too raise the Ethanol to its melting point is mathematically represented as
[tex]Q_1 = m * c_e * (T_m - T_i)[/tex]
=> [tex]Q_1 = 35.0 * 0.97 * ( -114 - (- 120) )[/tex]
=> [tex]Q_1 = 203.7 \ J[/tex]
Generally the heat of fusion of the Ethanol is mathematically represented as
[tex]Q_2 = n * F[/tex]
=> [tex]Q_2 =0.7809 * 5.02 *10^{3}[/tex]
=> [tex]Q_2 =3920 \ J[/tex]
Generally the heat required too raise the Ethanol to its boiling point is mathematically represented as
[tex]Q_3 = m * c_l * (T_b - T_m)[/tex]
=> [tex]Q_3 = 35.0 * 2.3 * ( 78 - (- 114) )[/tex]
=> [tex]Q_3 =15456 \ J[/tex]
Generally the heat of vaporization of the Ethanol is mathematically represented as
[tex]Q_4 = n * L[/tex]
=> [tex]Q_4 =0.7809 * 38.56 * 10^{3}[/tex]
=> [tex]Q_4 =29339 \ J[/tex]
Generally the heat required too raise the Ethanol from its boiling point to [tex]T_f[/tex] is mathematically represented as
[tex]Q_5 = m * c_l * (T_f - T_b)[/tex]
=> [tex]Q_5 = 35 * 2.3 * (120 - 78 )[/tex]
=> [tex]Q_5 = 3381 \ J[/tex]
Generally the total heat required is
[tex]Q = Q_1 + Q_2 + Q_3+Q_4 + Q_5[/tex]
=> [tex]Q = 203.7 + 3920 + 15456 +29339+3381[/tex]
=> [tex]Q = 52299.7 \ J[/tex]
PLEASEEE answer correctly! I will give u 10pts and brainleist if u get it right please:) (SCIENCE)
Answers
Answer:
The answer is 2
Explanation:
when viewed from earth number 2 would be a waning gibbous
How many moles of Mg(OH)2 will react with 2.5 mol HCI?
Answers
Answer:
1.25mole of Mg(OH)₂
Explanation:
The reaction is between Mg(OH)₂ and HCl, this is a neutralization reaction between an acid and a base.
Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O
The balanced reaction equation is given above.
2 mole of HCl reacts with 1 mole of Mg(OH)₂
So, 2.5mole of HCl will react with [tex]\frac{2.5}{2}[/tex] = 1.25mole of Mg(OH)₂
The number of moles of Mg(OH)₂ is given as 1.25mol
A tank containing oxygen, carbon dioxide, and nitrogen gases has a total pressure of 6.7
atm. If the O2 has a pressure of 3.0 atm and the carbon dioxide has a pressure of 1.2
what is the partial pressure of the nitrogen gas?
Answers
Answer:
P(N₂) = 2.5 atm
Explanation:
Given data:
Total pressure of gasses = 6.7 atm
Partial pressure of O₂ = 3.0 atm
Partial pressure of CO₂ = 1.2 atm
Partial pressure of N₂ = ?
Solution;
According to Dalton law of partial pressure,
The total pressure inside container is equal to the sum of partial pressures of individual gases present in container.
Mathematical expression:
P(total) = P₁ + P₂ + P₃+ ............+Pₙ
Now we will solve this problem by using this law.
P(total) = P(O₂) + P(CO₂) + P(N₂)
6.7 atm = 3.0 atm + 1.2 atm + P(N₂)
6.7 atm = 4.2 atm + P(N₂)
P(N₂) = 6.7 atm - 4.2 atm
P(N₂) = 2.5 atm
What type of compound is this?
Answers
Answer:sorry id ont known
Explanation:give m brianlest if you want
Please help I will mark brainy
Answers
Answer:freezing can occur
Source:trust me bro
2.Choose the correct order of the layers of the Earth from the outermost to the innermost layer
crust, asthenosphere, lower mantle, lithosphere, core
crust, lithosphere, asthenosphere, lower mantle, core
crust, asthenosphere, lithosphere, lower mantle, core
crust, lithosphere, lower mantle, asthenosphere, core
Answers
Answer:
A and C
Explanation:
I took the test
Which will diffuse the most? The particles with the
A. Least potential energy.
B. Most potential energy.
C. Least kinetic energy.
D. Most kinetic energy.
Answers
Answer:
B. Most potential energy
Explanation:
brainest plz
calculate the energy required to vaporize a chunk of ice at -25°C with the mass of 12.5kg
Answers
Explanation
Im not for sure if that’s correct so sorry if I get it wrong
which forces are contact forces? which r non contact forces/
magnetic force,friction,air resistance,gravitational force eletrostatic force and upupthrust
Answers
Which has the larger atomic radius Ga Or B
Answers
Answer:
Ga-135 is the largest atomic radius because B atomic radius is 85
a ball with a mass of 20 kg is accelerating at 4 m/s/s while being thrown . about how much force was used to throw the ball
Answers
Answer:
80 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 20 × 4
We have the final answer as
80 NHope this helps you
Answer:
80 n
Hope I helped
How many moles are in 2.43 x 1024 particles of Carbon Monoxide (CO)?
a.0.25 moles
b.4.04 moles
c.1.46 moles
d.2.53 moles
Answers
(2.43*10^24)*1/(6.022*10^23)
what are the three types of nuclear decay or reactions?
Answers
Answer:
alpha decay, beta decay, gamma decay
Can farmers simply plant more acres of crops to feed a growing population?
Answers
Answer:
I believe they can if it's a small town/village
Explanation:
Someone please help will mark as brainliest please answer all of the questions
Answers
Answer:
1.The main difference between SPECT and PET scans is the type of radiotracers used. While SPECT scans measure gamma rays, the decay of the radiotracers used with PET scans produce small particles called positrons. ... These react with electrons in the body and when these two particles combine they annihilate each other.
2 .A single photon emission computed tomography (SPECT) scan is an imaging test that shows how blood flows to tissues and organs. It may be used to help diagnose seizures, stroke, stress fractures, infections, and tumors in the spine.
3.Uses for PET scan include checking brain function; diagnosing cancer, heart problems, and brain disorders; examining blood flow to the heart; and determining spread of cancer and response to therapy. The use of PET scans may help doctors more accurately detect the presence and location of cancer cells.
4.Stress-only SPECT protocols resulting in lower dosimetry and less time in the imaging laboratory may be appropriate for many patients. PET perfusion imaging offers indisputably better images that are characterized by higher resolution, better attenuation correction, less scatter, and better contrast
Hope I wasn't too late.
Help answer fast please What is an example of homestasis?
A. You drink a bunch of redbull and your heart rate goes up
B. You run, your heart rate goes up, and then your heart rate goes back to its resting rate
C. A person has a fever
D. A person is thirsty but does not drink water
Answers
Answer:
c maybe sorry if its wrong
Explanation:
Write one paragraph explaining what you have learned so far about Kinetic and Potential Energy.
(will give brainliest)
Answers
Answer: Energy stored in an object due to its position is Potential Energy. The energy that a moving object has due to its motion is Kinetic Energy. All forms of kinetic energy are the result of a previous state of potential energy. For example, the stored chemical potential energy of a battery converts to electrical kinetic energy to transport electricity to a light bulb, which radiates thermal kinetic energy. Potential energy is the energy that is stored in an object due to its position relative to some zero position. An object possesses gravitational potential energy if it is positioned at a height above (or below) the zero height.
which two elements make up the main structure of an organic compound?
A. Carbon and oxygen
B. Nitrogen and oxygen
C. Carbon and hydrogen
D. hydrogen and sulfur
Answers
Answer:
b nitrogen&oxygen
Explanation:
i'm built different
Ch 8 Test
Circle the best answer to each question
The temperature of a roast is checked to see if it has met its critical limit of 145 F. for 4 min. This is an example of which HACCP principle?
Verification
Monitoring
Record keeping
Hazard analysis
2. The temperature of a pot of beef stew is checked during holding. The stew has not met the critical limit and is thrown out according to house policy. Throwing out the stew is an example of which HACCP principle?
Monitoring
Verification
Hazard analysis
Corrective action
3. The deli serves cold sandwiches in a self serve display. Which step in the flow of food would be a critical control point?
Storage
Cooling
Cooking
Reheating
4. What is the first step in developing a HACCP plan?
Identify corrective actions
Conduct a hazard analysis.
Establish monitoring procedures.
Determine critical control points
5. What is the purpose of a food safety management system?
Keep all areas of the facility clean and pest free
Identify, tag, and repair faulty equipment within the facility
Identify and control possible hazards throughout the fowo of food
Document and use the correct methods of purchasing and receiving food
6. Reviewing Temperature logs and other records to make sure that the HACCP plan is working as intended is an example of which HACCP principle?
Monitoring
Verification
Hazard Analysis
Record Keeping
7. A Chef sanitized a thermometer probe and then checked the temperature of minestrone soup being held in a hot holding unit. The temperature was 120 F., which did not meet the operations critical limit of 135 F. The chef recorded the temperature in the log and reheated the soup to 165 F. for 15 sec. Which was the corrective action?
Reheating the soup
Checking the critical limit
Sanitizing the thermometer probe
Recording the temperature in the log
8. What does an operation that wants to smoke food as a method of preservation need to have before processing food this way?
Food Safety certificate
Crisis management plan
Master cleaning schedule
Variance from the local regulatory authority
Answers
Answer:
so you like fortnite but it's bad rjfbfbhrr
What separates the inner planets from the outer planets in our solar system?
()Comet Belt
()Asteroid Belt
()Their differences
()Distance
Help plss!!
Answers
Answer:
the answer is B Astroid Belt
Aqueous solutions of sodium carbonate and magnesium chlorate are mixed
Answers
Explanation:
You're mixing magnesium nitrate, Mg(NO3)2 , and sodium carbonate, Na2CO3 , two soluble ionic compounds that dissociate completely in aqueous solution to form cations and anions.
Someone please help will mark as brainliest
Answers
Answer:
a1
The main difference between SPECT and PET scans is the type of radiotracers used. While SPECT scans measure gamma rays, the decay of the radiotracers used with PET scans produce small particles called positrons. A positron is a particle with roughly the same mass as an electron but oppositely charged.
Explanation:
a2
While imaging tests such as X-rays can show what the structures inside your body look like, a SPECT scan produces images that show how your organs work. For instance, a SPECT scan can show how blood flows to your heart or what areas of your brain are more active or less active.
a3
PET and SPECT have been extensively evaluated as diagnostic procedures for dementia. Substantial progress has been made in developing radioligands that bind to amyloid deposits in the brain, which should provide new opportunities for early diagnosis and treatment monitoring in Alzheimer's disease
a4
What are the disadvantages of spect as compared to pet?
However, SPECT has issues, including long scan times and low-resolution images prone to artifacts and attenuation. Some artifacts can easily be misidentified as perfusion defects. SPECT also does not provide a quantifiable estimate of the blood flow, whereas PET does, experts say.
A bottles contains 3.100 mL of a liquid. The mass of the liquid is 2.060 g. What is the density of the liquid? (BE SURE TO
SHOW ALL THREE PARTS: EQUATION, WORK, AND PROPER FULL ANSWER.
Answers
Answer:
0.66 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
From the question we have
[tex]density = \frac{2.06}{3.10} \\ = 0.664516..[/tex]
We have the final answer as
0.66 g/mLHope this helps you
What are the differences and relationships between a dependent variable and an independent variable?
Answers
Explanation:
A dependent variable depends on the independent variable. The independent variable is what you usually control in a experiment.
What happens when a virus becomes latent?
Answers
Answer:
the full viral genome is retained in the host cell, but its expression is dramatically restricted, such that few viral antigens and no viral particles are produced.
Explanation:
what is an extensive prperty of matter
Answers
Answer:
Volume
Mass
Size
Weight
Length
Explanation:
Extensive properties do depend on the amount of matter that is present. An extensive property is considered additive for subsystems. Examples of extensive properties include:
Volume
Mass
Size
Weight
Length
A 0.040 kg ball tied to a string moves in a circle that has a radius of 0.700 m. If the ball is accelerating at 43.2 m/s2, what is the tangential velocity of the ball?
Answers
Answer: 30.24 m/s
Explanation:
Got it right on test