Answer:
Phosphorus
Explanation:
Atomic number of phosphorus is 15. Its electronic configuration is 2,8,5. So, it needs 3 electrons to fulfill its outermost shell and attain stability. Thus, its valency is 3.
HURRY!!!!!! HELP PLEASEEE
To begin the experiment, 1.65g of methane CH4 is burned in a bomb calorimeter containing 1000 grams of water. The initial temperature of water is 18.98oC. The specific heat of water is 4.184 J/g oC. The heat capacity of the calorimeter is 615 J/ oC . After the reaction the final temperature of the water is 36.38oC.
2. Calculate the change in temperature, ΔT. Show your work. (1pt)
3. Calculate the heat absorbed by water. Use the formula qwater = m • C • ΔT
Show your work (2pts)
4.Calculate the heat absorbed by the Calorimeter. Use the formula:
qcal = Ccal • ΔT Show your work. (2pts)
5. The total heat absorbed by the water and the calorimeter can be calculated by adding the heat calculated in steps 3 and 4. The amount of heat released by the reaction is equal to the amount of heat absorbed with the negative sign as this is an exothermic reaction. (2pts)
a.Using the formula ΔH = - (qcal + qwater ) , calculate the total heat of combustion. Show your work.
b. Convert heat of combustion (answer from part a) from joules to kilojoules. Show your work.
6. Evaluate the information contained in this calculation and complete the following sentence: (2pts)
This calculation shows that burning _______ grams of methane [TAKES IN] / [GIVES OFF] energy (Choose one).
7. The molar mass of methane is 16.04 g/mol. Calculate the number of moles of methane burned in the experiment. Show your work. (2pts)
8. What is the experimental molar heat of combustion in KJ/mol? Show your work. (2pts)
9. The accepted value for the heat of combustion of methane is -890 KJ/mol . Explain why the experimental data might differ from the theoretical value in 2-3 complete sentences. (2pts)
10. Given the formula:
% error= |(theoretical value - experimental value)/theoretical value)| x 100
Calculate the percent error. Show your work. (2pts)
The calorimter is equal to the heat released by the reaction. Calculate the heat released by the reaction.
What is the reaction?The reaction to the news can vary depending on who you are speaking to. For some, the news may be welcomed as a sign of progress and a move in the right direction. Others may be apprehensive, uncertain of the potential outcomes or changes that may come as a result. Some may be angry and frustrated, feeling as though the news has been a long time coming and they have not been given a say in the matter.
1. ΔT = 36.38oC - 18.98oC = 17.4oC
2. qwater = m • C • ΔT
qwater = (1000g)(4.184J/g oC)(17.4oC)
qwater = 71376.8 J
3. qcal = Ccal • ΔT
qcal = (615J/ oC)(17.4oC)
qcal = 10666.1 J
4. qreaction = qwater + qcal
qreaction = 71376.8 J + 10666.1 J
qreaction = 82042.9 J
To learn more about reaction
https://brainly.com/question/25769000
#SPJ1
Convert 1.65 moles of nitrogen gas at STP to liters.
What is the coefficient of the scientific notation answer ? What is the exponent of the scientific notation answer ? How many significant figures are there in the answer ? What is the right most significant figure in the answer ?
Answer:
See explanation
Explanation:
We know that 1 mole of a gas occupies 22.4 L
Hence, 1.65 moles of nitrogen gas occupies 1.65 moles * 22.4 L/1 mole = 36.96 L or 3.696 * 10^1 L = 3.70 * 10^1 L
The exponent of the scientific notation answer = 1
The significant figures there are in the answer = 4
The right most significant figure in the answer = 2
Complete the following molecular models to represent balanced equations by
drawing additional molecules but not changing the identity of them. When you are
done, the total number of atoms of each element on the reactant side of the equation
must equal the total number of atoms of the same elements on the product side.
a)
Answer:
I do not know the Answer I'm just trying to get my point
Explanation:
Thank you
Is heat a from of kinetic or potential energy?
Answer:
its made up of both but I would probably say kinetic
Explanation:
Y’all Someone plz help me with these problems.
Girl I will report if u troll or link
Answer:
A. 650 moles of sulphur.
B. 30 g of FeS₂
Explanation:
The balanced equation for the reaction is given below:
Fe + 2S —> FeS₂
From the balanced equation above,
1 mole of Fe reacted with 2 moles of S to produce 1 mole of FeS₂.
A. Determination of the mole of sulphur needed for the reaction.
From the balanced equation above,
2 moles of S reacted to produce 1 mole of FeS₂.
Therefore, Xmol of S will react to produce 325 moles of FeS₂ i.e
Xmol of S = 2 × 325
Xmol of S = 650 moles
Thus, 650 moles of sulphur are needed for the reaction.
B. Determination of the mass of FeS₂ produced by the reaction of 0.5 mole of sulphur.
From the balanced equation above,
2 moles of S reacted to produce 1 mole of FeS₂.
Therefore, 0.5 mole of S will react to produce = (0.5 × 1)/2 = 0.25 mole of FeS₂.
Finally, we shall determine the mass of 0.25 mole of FeS₂. This can be obtained as follow:
Mole of FeS₂ = 0.25 mole
Molar mass of FeS₂ = 56 + (32×2)
= 56 + 64
= 120 g/mol
Mass of FeS₂ =?
Mass = mole × molar mass
Mass of FeS₂ = 0.25 × 120
Mass of FeS₂ = 30 g
Thus, 30 g of FeS₂ were obtained from the reaction.
help i give more point this time
Answer:
It's a type of chemical bond that emerges because of electrostatic force between electrons and positive metal charges.
Explanation:
I don't know if this is what you are looking for but i don't mind if you copy it.
Sea, sand, sky, palms – made almost all of
Answer:
sup
Explanation:
Which of these cannot be
a source of centripetal force?
A. mass
B. friction
C. electric force
D. gravity
Answer:
D. GravityExplanation:
Gravity cannot be a source of centripetal force. Gravity is the force of attraction from between all masses in the universe; especially the attraction of the earth’s mass for bodies near its surface; “gravitation cannot be held responsible for people falling in love” with Albert Einstein.
It manner that is serious and solemn. A solemn and dignified feeling.
Therefore, the correct answer is d. gravity.
What is the mass of 1.50 mole of (NH4)2CO3?
Answer:
144.12873
Explanation:
Hope this helps you
-----------------------------------------------------------------------------------------------------------------
回答：
144.12873
説明：
これがお役に立てば幸いです
Answer:
96gm/mole
Explanation:
(NH 4)2CO 3 =2×18+12+3×16=96gm/mole
PLEASE ANSWER THIS ASAP I WILL MARK YOU THE BRAINLIEST
The actual subject is Science but they dont have that as a option in pick a subject
Answer:
up to down(1 to 6)
Explanation:
speed:
1,3,4
Velocity:
everything except 1,3,4
Copper(Ii) Iodate + Potassium Carbonate = Potassium Iodate + copper(I)carbonate into a formula equation ?
Answer:
Cu(IO3)2 + K2CO3 → 2KIO3 + CuCO3
How much heat does it take to raise 100g of aluminum (c= .9 J/gC) from 12.5C to 31C?
Answer:
When two substances having different temperatures are introduced or kept together, heat energy, Q, flows from a substance at higher temperature to a substance at lower temperature. Also, heat continues to be transferred until their temperatures are equalized, at which point the substances are in thermal equilibrium. In a closed system, the amount of energy lost is equal to but opposite the amount of energy gained.
Explanation:
Describe how the size of the sun compares to the sizes of the other stars.
Answer:
The sun's circumference is about 2,713,406 miles (4,366,813 km). It may be the biggest thing in this neighborhood, but the sun is just average compared to other stars. Betelgeuse, a red giant, is about 700 times bigger than the sun and about 14,000 times brighter.
Explanation:
looked it up
Explanation:
The sun's circumference is about 2,713,406 miles (4,366,813 km). It may be the biggest thing in this neighborhood, but the sun is just average compared to other stars. Betelgeuse, a red giant, is about 700 times bigger than the sun and about 14,000 times brighter
plz help i’m gonna cry i’m in class rn
Answer:
if ur gonna cry then just dont cry its simple logic guyss!!!!!!!!!!!!
Explanation:
1. Which of the following would not be a good way to describe a body system?
A. Body systems are like computer programs that have to communicate with each
other in order to make the computer work.
B. Body systems are like runners in a marathon who each run alone and don't need the
other runners to finish the race.
C. Body systems are like machines with many different moving parts.
D. Body systems are like individual parts of one big story.
Answer:
the answer would be b
Explanation:
the body sytsem needs to depend on eah other in order to work
Body systems are like runners in a marathon, who each run alone and don't need the other runners to finish the race, is not a good way to describe a body system, hence option B is correct.
How body systems work together?Your digestive tract takes nutrients and water from the food you eat in to your body. The body's cells receive oxygen, water, and nutrients through your circulatory system.
Your skin, excretory system, and respiratory system all function to remove wastes from your cells.
Your body's many systems depend on one another to function properly. While your heart's muscles require oxygen from your lungs to beat, your respiratory system depends on your circulatory system to distribute the oxygen it collects.
Therefore, option B is correct.
Learn more about body systems, here:
https://brainly.com/question/13258877
#SPJ2
Excess Fe reacted with 650mL of 0.75M H3PO4. What mass of hydrogen gas was produced? g H2
Fe + H3PO4 à Fe3(PO4)2 + H2
This is an oxidation-reduction (redox) reaction:
6 HI + 6 e- → 6 H0
(reduction)
3 Fe0 - 6 e- → 3 FeII
(oxidation)
H3PO4 is an oxidizing agent, Fe is a reducing agent
Answer: see pics. Hope it makes sense.
Explanation:
Please answer as many question as possible ty
a student needs to use 0.485 moles of sodium chloride in an experiment how many grams should he measure out in grams. (show work)
Answer:
the answer is 28.4 g NaCl
Explanation:
Jose was driving to New York City. He traveled 100 miles in the first hour of the trip and 20 miles in the last hour of his trip. Which can we
say about Jose's drive? (speed = distance = time)
A. Jose drove less than 120 miles.
B. Jose drove faster the first hour of his drive.
C. Jose drove slower the first hour of his drive.
D. Jose drove the same speed for the entire drive.
Answer:
b
Explanation:
he drove 5x faster than the time was when he was on the last hour (maybe caught in traffic or wasn't in a rush)
I NEED HELP PLEASE ASAP THANK YOU!
Answer:
K = °C +273
°C = K - 273
1. 59 °C.
2. 300K.
5. 673K
6. 927 °C
A bottle contains 2.5 moles of KOH dissolved in water, and the molarity of the solution is 0.16 M.
What volume of solution is in this bottle?
Answer:
V = 15.6 L
Explanation:
Hello there!
In this case, according to the definition of molarity in terms of the moles of solute divided by the volume of the solution, it is possible for us to write:
[tex]M=n/V[/tex]
Thus, given the moles and concentration of the solution, we can find the volume as shown below:
V=n/M
Therefore, we plug in the given data to obtain:
V = 2.5mol /(0.16mol/L)
V = 15.6 L
Best regards!
What is the poh of a solution with a ph of 1.30? PLZZ ANSWER
Answer:
12.70
Explanation:
How does Gibbs free energy predict spontaneity?
O A. If AG > 0, the reactigais spontaneous.
B. If AG = 0, the reaction is spontaneous.
C. If AG < 0, the reaction is spontaneous.
O D. If AG = TAS, the reaction is spontaneous.
Answer:
C
Explanation:
plz mark brainliest
Gibbs free energy predict spontaneity if G < 0, the reaction is spontaneous and the correct statement is option C.
What is Gibbs Free Energy?Gibbs free energy is a quantity that is used to measure the maximum amount of work done in a thermodynamic system when the temperature and pressure are kept constant.
Gibbs free energy is denoted by the symbol ‘G’. Its value is usually expressed in Joules or Kilojoules.
Gibbs free energy can be defined as the maximum amount of work that can be extracted from a closed system.
Gibbs free energy to determine the spontaneity of a process.
Therefore, Gibbs free energy predict spontaneity if G < 0, the reaction is spontaneous and the correct statement is option C.
Learn more about Gibbs free energy, here:
https://brainly.com/question/20358734
#SPJ5
What happens when you mix calcium chloride and hydrogen peroxide?
Answer:
Explanation: When chlorine reacts with hydrogen peroxide, hydrogen peroxide falls apart into water and oxygen. Chlorine gas hydrolyses into hypochlorous acid (, which subsequently into hypochlorite ions . The reaction between hydrogen peroxide and hypochlorite takes place very quickly.
Regions that receive up to 20 inches of rainfall per year are referred to as __________ because they receive more precipitation than most deserts.
semiarid deserts
polar deserts
coastal deserts
subtropical deserts
Answer:
The answer is in fact semi-arid deserts. This just serves as a confirmation cause sometimes the answers be wrong.
Semiarid deserts is the region that receive up to 20 inches of rainfall per year.
What is Rainfall?
This is defined as the amount of precipitation in the form of water droplets that falls onto the surface of Earth from the clouds due to gravity influence.
Semi-arid desert receive more precipitation which is around 20 inches of rainfall than most deserts.
Read more about Semi arid deserts here https://brainly.com/question/3363067
I need help with number 17 pls someone pls ???
Answer:
can you pls say what subject it is pls and thank u
Explanation:
Answer:
glass cup as it can trap oxygen from getting in and out meaning that the fire can't grow
Help!!!!
I can’t understand this question
Answer:
free points!!!!!!!!!!!!!!
If you start with 13 mole H2O and 50 grams of O2 what is the percent yield of H202 if 100 grams of H202 is actually made?
Answer:
94.1 %
Explanation:
We firstly determine the equation:
2H₂O + O₂ → 2H₂O₂
2 moles of water react to 1 mol of oxygen in order to produce 2 moles of oxygen peroxide.
We convert the mass of oxygen to moles:50 g . 1mol /32g = 1.56 mol
Certainly oxygen is the limiting reactant.
2 moles of water react to 1 mol of oxygen.
13 moles of water may react to 13/2 = 6.5 moles. (And we only have 1.56)
As we determine the limiting reactant we continue to the products:
1 mol of O₂ can produce 2 moles of H₂O₂
Then 1.56 moles of O₂ will produce (1.56 . 2) = 3.125 moles
We convert the moles to mass: 3.125 mol . 34 g/mol= 106.25 g
That's the 100% yield or it can be called theoretical yield.
Percent yield = (Yield produced / Theoretical yield) . 100
(100g / 106.25 g) . 100 = 94.1 %
Which of the following adaptations found in animals in deciduous forests protects against predators?
a.
fat storage
b.
migration
c.
hibernation
d.
camouflage
Please select the best answer from the choices provided
A
B
C
D
Should be D
Answer:
The answer is D. Camouflage
Answer:
THE ANSWER IS D) CAMOUFLAGE
What is metallurgy?
A. Science of minerals.
B. Science of working with metals.
C. Science of breaking down rock.
D. Science of volcanoes.
Answer:
B science of working with metals