# which of the following is a chemical reaction? A) propane forms a flame and emits heat as it burns. B) Acetone feels cold as it evaporates from the skin. C) Bubbling is observed when potassium carbonate and hydrochloric acid solutions

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1. ## More Chem

Consider the combustion of propane. Delta H is -2221 kJ. Assume all heat is from combustion of propane. What mass of propane must be burned in order to furnish this amount of energy assuming the heat transfer process is 60% efficient.

2. ## Chemistry

Consider the combustion of propane: C3H8(g)+5O2(g) yields 3CO2(g) + 4H2O(l) delta H= -2221 kJ Assume that all of the heat comes from the combustion of propane. Calculate delta H in which 5.00g of propane is burned in excess oxygen at constant pressure.

3. ## chemistry

Am I correct? Deterioration of buildings, bridges, and other structures through the rusting of iron costs millions of dollars everyday. Although the actual process also requires water, a simplified equation (with rust shown as iron(III) oxide (Fe2O3) is:

4. ## Chemistry

heat of combustion of propane c3h8, 2220KJ/mol. the specific heat of copper is 0.385 J/g*C. How many grams of propane must be burned to raise the temperature of a 10.0kg block of copper from 25.0 C to 65.0 C,assuming none of the heat is lost to the

5. ## chem

which of the following is a chemical reaction? A) propane forms a flame and emits heat as it burns. B) Acetone feels cold as it evaporates from the skin. C) Bubbling is observed when potassium carbonate and hydrochloric acid solutions are mixed. D) Heat is

6. ## chemistry

In the reaction between formic acid (HCHO2) and sodium hydroxide, water and sodium formate (NaCHO2) are formed. To determine the heat of reaction, 75.0 mL of 1.07 M HCHO2 was placed in a coffee cup calorimeter at a temperature of 20.8 °C, and 45.0 mL of

7. ## chemistry

consider the following reaction: C3H8 (g)+ 5O2 (g)--> 3CO2 (g)+ 4H20 (g) Delta H = -2440kJ The heat of formation of CO2 is -390 kJ/mol and the heat of formation of H2O is -240 kJ/mol. What is the heat of formation of propane?

8. ## Chemistry

Propane, C3H8, is a common fuel gas. Use the following to calculate the grams of propane you would need to provide 383 kJ of heat. C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) ΔH = −2043 kJ

9. ## Chemistry

1.) The the following reaction is: BaCO3 --> BaO + CO2 Decomposition reaction Single replacement reaction Combustion Reaction Synthesis Reaction Double replacement reaction 2.) When magnesium is burned in the presence of oxygen, it produces magnesium oxide

10. ## ap chem

The heat of combustion of propane is -2,220.1 kJ/mol calculate the heat of formation, delta Hf, of propane given that delta Hf of H20= -285.3 kJ/mol and delta Hf of CO2 = -393.5 kJ/mol

11. ## General chemistry

Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 16.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.

12. ## chemistry

Examine the scenario. Chemical Reaction A and Chemical Reaction B involve the same two reactants. Chemical Reaction A is performed in a hot container, while Chemical Reaction B is performed in a cold container. Which of the answer choices correctly

13. ## chemistry

If all the energy obtained from burning 1.23 pounds of propane (fuel value is 11.09 kcal/g) is used to heat 125.0 kg of water at an initial temperature of 21.8 °C, what is the final temperature? Hint: The heat, q, released by burning propane is absorbed

14. ## science

why does a candle appear to go out when a copper coil is placed over the flame? Combustion requires three things: fuel (wax here), oxygen (air here), ignition temperature (a match here probably). Remove one and the combustion stops -- that's the principles

15. ## Chemistry

What change do you expect if the value of the reaction quotient is greater than the value of the equilibrium constant? A- Rate of the forward reaction is greater than the rate of the reaction B- The rate of the forward reaction is less than the rate of the

16. ## Chemistry

When your body breaks down sugar completely, how much heat is released compared to burning the same amount of sugar in a flame? The body releases___ less heat than the flame*** more heat than the flame same amount of heat as a flame the body releases so

17. ## AP Chemistry

1) Calculate the volume of air at 30 degrees C and 1.00 atm that is needed to burn completely 10.0 grams of propane. Assume that air is 21.0 percent O2 by volume. 2) Assuming all of the heat evolved in burning 30.0 g of propane is transferred to 8.00 kg of

18. ## Chemistry

What does the symbol ∆H stand for? one Calorie given off by a reaction the heat capacity of a substance*** the heat of a reaction for a chemical reaction the specific heat of a substance

19. ## Chemistry

Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 19.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.

20. ## physical science with earth science

Write a balanced chemical equation for the reaction for propane C3H8 burning in oxygen to for carbon dioxide and water vapor

21. ## Science

7. Which of the following changes gives no evidence that a chemical reaction has taken place? A cube of solid forms a puddle of liquid. A certain liquid is added to a solid, and bubbles of gas form. Two liquids are mixed, and a precipitate forms. Heating a

22. ## AP chemistry

Propane (C3H8) is burned in oxygen to pro- duce carbon dioxide and water. The heat of combustion of propane is -2012 kJ/mole. How much heat is given off when 3.0 mol C3H8 are reacted with 10.0 mol O2?

23. ## Chemistry

How much heat would be released by the complete combustion of 35.0 g of propane, C3H8? (The molar mass of propane is 44.09 g/mol.) C3H8 + 5O2 --> 3CO2 + 4H2O LaTeX: \Delta Δ H = -2044 kJ

24. ## Chemistry

A 1.55-g sample of propane, C3H8, was burned in a bomb calorimeter whose total heat capacity is 12.3 kJ/°C. The temperature of the calorimeter plus its contents increased from 21.36°C to 27.69°C. What is the heat of combustion per gram of propane?

25. ## chemistry

If 10L each of propane and oxygen are combined at the same temperature and pressure, which gas will be left over after reaction? What volume of that gas will remain? The answer is 8 L of Propane Tried for a while but I don't understand how answer books

26. ## Chemistry

Propane, C3H8, is a common fuel gas. Use the following to calculate the grams of propane you would need to provide 369 kJ of heat. C3H8 (g) + 5O2 (g) --> 3CO2 (g)+ 4H2O (g) ; Delta H = -2043kJ

27. ## Physical Science

Which of the following statements are true about chemical reactions? Check all that apply. A. Reactants are on the right when writing a chemical reaction. B. Products are produced in a reaction. C. Reactants are present at the end of a reaction. D.

A water heater is fueled by the combustion of propane as described by the following reaction: C3H8(g) + 5 O2(g) --> 3 CO2(g) + 4 H2O(l) a) Determine how much heat is released if 11.2 moles of propane are burned at 298 K and at a constant pressure of 1.00

29. ## chemistry

Propane gas is used to heat a tank of water. If the tank contains 200 L of water, what mass of propane will be required to raise its temperature from 20 degrees C to 65 degrees C. The heat of combustion for propane is -2220 kJ/mol.

30. ## Chemistry

Which information can you determine about a chemical reaction from a complete chemical equation? - how much energy is released as heat - how fast the reaction occurs - formation of a solid precipitate - color of the products

31. ## Chemistry

Regarding Flame Tests, why do you have to subject the sample to a flame? Which part of the Bunsen Burner is hottest? Why is it necessary to hold the loop in this part of the flame? What do you think will happen if you perform the flame test on a solution

32. ## Chemistry

the molar heat of combustion of propane is -2.2*10^3 kJ. how many grams of propane would have to combusted to raise 1.0kg of water from 22.0 C to 100.0 C?

33. ## Science

What type of energy from the Sun do plants use to make their own food? A.Chemical Energy B.Sound Energy C.Light Energy D.Heat Energy C? An MP3 player uses the chemical energy in a battery to produce electricity energy. The electrical energy makes the

34. ## chemistry

Which of the following minor products could not arise from the halogenation reaction below? isobutane + Br2 ----> 1-bromo-2-methyl propane + HBr + minor products a)2,5 dimethylhexane b)2 bromo-2 methyl propane c)1,3 dibromo, 2 methyl propane d) 2,4

35. ## chemistry

What is the difference between biochemical, pharmaceutical, and diagnostic chemical reactions in healthcare? What is a specific example that exists for each of these chemical reaction types above and why might it be of importance to healthcare

36. ## Biochem 12

Calculate the energy released per gram of propane when it is burned in a combustion reaction. The chemical formula for propane is C3H8.

37. ## Chemistry help (DrBob222)

propane (c3h8) is burned in oxygen to produce carbon dioxide and water. The heat of combustion of propane is -2012 kJ/mole. How much heat is given off when 3.0 mol C3H8 are react with 10.0 mol O2? Thanks, and please if possible show all steps!

38. ## chemistry

The combustion of propane is given by the following reaction: C3H8 (g) + 5 O2 (g) ---> 3 CO2 (g) + 4 H2O (g) If 5.00 L of propane are burned in in the presence of excess O2, how many liters of carbon dioxide will be formed?

39. ## Science

When you put your hand near a candle, you feel heat directly over the flame but cool on the sides of the flame. Why does this difference occur? I think because of convection the warmer air rises and the cooler air sinks.

40. ## chemistry

Propane reacts with oxygen in a combustion reaction. What volume of carbon dioxide gas is formed when 20 L of propane are reacted with 55.7 L of oxygen?

41. ## Science

Which of the following best describes the result of using a catalyst in a chemical reaction? A. The yield of product is increased. B. A more desirable product is often formed. C. A greater amount of heat energy is released by the reaction. D. The reaction

42. ## chemistry

Propane fuel is used in BBQs. Use the following reaction to determine how many moles of oxygen gas are needed to react with 1.6 moles of propane gas. C3H8(g)+5O2(g) --------> 4H2O(g)+ 3CO2(g)

43. ## Chemistry

Atom-Particle that cannont be divided in half becasue it is in its smallest form. Reactants-Substances that exist before the reaction begins. Endothermic Reaction-take in, or absorb heat energy. Exothermic Reaction- Release Heat energy Inhibitor-makes a

44. ## A2 Chemistry

This question is about the unnecessary production of carbon dioxide Outdoor flames, such as patio heaters and the Olympic flame, contribute to global warming. This is not only due to the heat released, but also due to the carbon dioxide produced from the

45. ## chemistry

when you hold a hydrogen filled pipet bulb horizontally with its mouth about 1 cm from a falme while gently squeezing what would you observe? a. the flame goes out b. a gentle pop and the flame may have been blown out c. the flame got bigger d. nothing

46. ## chem!

Calculate the heat of reaction for the incomplete combustion of 67.0g propane producing carbon monoxide gas and water vapour. how would I go about and do this question? What are you studying? Do you know how to use the thermodynamic tables (delta Ho, etc).

47. ## Some Chemistry Questions

I got three questions. If you were making a tool used to handle live electrical wires, which class of materials would you most likely use? ***Semimetals Metalloids Nonmetals Metals Which of the following changes gives no evidence that a chemical reaction

48. ## Chemistry (Check)

In a calorimeter experiment done at constant pressure in which all the heat from a chemical reaction was absorbed by the surrounding water bath, the temperature of the water went up by 2.31 K. If the size of the water bath was 200 g, what was the amount of

49. ## engineering

I need help with my Fire Engineering homework. What is the heat release rate of a flame measuring five feet in height assuming the flame is in the center of a room?

50. ## Chemistry

In a certain chemical reaction, 20.40kJ of heat are evolved. The volume of the reaction is 36.8dm^3 and that of the product is 9.6dm^3. Calculate the change in internal energy for the reaction. Assume the reaction is at ATM pressure.?

51. ## chemistry

How many grams of propane (C3H8) must be burned to release 3600kJ of energy? Standard Heat of combustion for Propane= -2220 kJ/Mole

52. ## chemistry

Could someone please tell me if I did this question correctly? An incomplete combustion reaction of 12.125 grams of propane proceeds as follows: 2C3H8 + 11O2 = 3CO2 + 4H2O + 2CO + C(s).How many grams of solid carbon residue are produced as a product? my

53. ## Chemistry

Could someone please tell me if I did this question right? An incomplete reaction of 12.125 grams of propane proceeds as follows. 2C3H8+11O2 --> 3CO2+4H2O+2CO+C(s) How many grams of solid carbon residue are produced as a product? My answer: Step 1)

54. ## Chemistry

Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 15.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.

55. ## Chemistry

Many portable gas heaters and grills use propane, C3H8(g). Using enthalpies of formation, calculate the quantity of heat produced when 17.0g of propane is completely combusted in air under standard conditions. Assume that liquid water is forming.

56. ## chemistry

Does an insoluble solid dissociate into ions? Is the reaction reversible? Will an equilibrium reaction form when a chemical reaction forms an insoluble solid? Why, or why not?

57. ## biology

Which of the following is true about the relationship between energy and chemical reactions? Activation energy is required for a chemical reaction to occur. Activitation energy is not necessary in a chemical reaction which releases energy. Chemical bonds

58. ## physics

Find the heat flux due to radiation from a gasoline pool fire whose flame is 3 m tall with a 1 m diameter, and it is 3.5 m away from a target fuel. Assume e = 0.98 with a flame temperature of 1,300 K. Solve this problem by determining the configuration

59. ## Chemistry

using the balanced reaction equation for the combustion of propane, determine the number ofmoles of oxygen that would react with.50 mol propane and the number of moles of carbon dioxide that would be produced?

60. ## Science

Many portable gas heaters and grills use propane, C3H8(g), as a fuel. Using standard enthalpies of formation, calculate the quantity of heat produced when 11.90 g of propane is completely combusted in air under standard conditions. I got -600 kj but its

61. ## Physics- Energy Released In Chemical Reaction

The reaction between two hydrogen isotopes is shown below: 2H + 3H → 4He + n + energy released The energy released in this reaction is: a.equal to that in a fission reaction b.equal to that in a chemical reaction. c.less than that in a chemical reaction.

62. ## Chemistry

A small bottle of propane gas (C3H8) contains 400.0 grams of propane. When the propane is burned in oxygen, how many moles of each product are formed?

63. ## Minoxidil

So, I'm doing a research project for my chemistry class, and one of the parts that I have to answer is the chemical reaction of the substance that I'm researching. But there's a problem. I've searched every single website regarding minoxidil, but I cannot

64. ## Chemistry

How many moles of propane are expected from the complete reaction of 82.8 g of propene? How many grams of propane are expected from the complete reaction of 101 g of propene? Kyle-- Here is a problem I worked last night for Kira (about half way down the

65. ## Physics

Just as no mechanical device can be 100% efficient, no heat engine can transfer 100% of its heat to a single object. Some of the heat energy must be wasted (released into the environment). We have a heat engine that produces 150 J of heat, does 40 J of

66. ## Chemistry

the heat of combustion of propane is -5.47MJ/mol. there is 1.50kg of propane available to burn. how many litres of water could be heated from 18.0 degrees Celcius to 63.0 degrees Celcius using the heat from the burning propane. assume that all heat lost by

67. ## Chemistry Help!!

Propane(C3H8), the major component of LP game, is often used as heating and cooking fuels in homes. When propane is burned( reacted with oxygen), CO2(g) and H2O(g) are produced. 1) Write an equation for the reaction and calculate the enthalpy change for

68. ## Physics

Suppose a flame of a gas burner stove emits light just like a blackbody.The flame appears blue,emiting most of the light as a wave length of 475 nanometers. what is the temperature of the flame. How do I solve this?

69. ## Physics

I had posted this question once before, but no one helped me on this one. So I am posting this question again. Suppose the flame of a gas burner stove emits light just like a blackbody. The flame appears blue emiting most of the light at a wave length of

70. ## chemistry 116

The thermite reaction demonstrated in class requires high temperatures to start the reaction. A simple open flame is not enough to start the reaction. Once the reaction is going, then it generates enough heat to keep the reaction going. According to the

71. ## CHEM

Will you please tell me if these are right? Write the symbol of the caton or anion that give(s) the following reaction:? 1. Forms a precipite with AgNO3 that does not dissolve in HNO3 2. Forms a gas with HCl 3. Give a bright, yellow-orange flame test 4.

72. ## physics

Suppose the fame of a gas burner stove emits light just like a blackbody. The flame appears blue,emiting most of its light at a wave lengh of 475nanometers. what is the temperature of the flame? How do I solve this?

73. ## To: Bobpursely

You helped me with my observations yesterday, but I need help with my questions as well. I tried to answer as many as I could by myself, but I'm having difficulties understanding some. Pointing me towards the right direction would be helpful, thanks.

74. ## Biology

In an ecosystem, when energy is given off as heat, does it change forms from chemical substances to heat? Or is it something different?

Homework - Pick 4 out of the 6 forms (types) of energy and gives an example of each from your house. Types/Forms of Energy 1. Mechanical Energy 2. Electrical Energy 3. Electromagnetic Energy 4. Heat Energy 5. Chemical Energy 6. Nuclear Energy I'm picking

76. ## Science

Consider the combustion of propane: C3H8(g)+5O2(g) yields 3CO2(g) + 4H2O(l) delta H= -2221 kJ Assume that all of the heat comes from the combustion of propane. Calculate delta H in which 5.00g of propane is burned in excess oxygen at constant pressure.

77. ## Chemistry

Regarding Flame Tests, why do you have to subject the sample to a flame? Which part of the Bunsen Burner is hottest? Why is it necessary to hold the loop in this part of the flame? What do you think will happen if you perform the flame test on a solution

78. ## chemistry

When two solutions are mixed and a new color is observed, is this color change an indication that a chemical reaction has occurred? Explain. It is not possible to directly observe chemical bonds breaking and forming during a reaction, molecules and atoms

79. ## ap chemistry

Propane (C3H8) is burned in oxygen to pro- duce carbon dioxide and water. The heat of combustion of propane is -2012 kJ/mole. How much heat is given off when 3.0 mol C3H8 are reacted with 10.0 mol O2? 1. 4024 kJ 2. 2012 kJ 3. 916 kJ 4. 1555 kJ 5. 5122 kJ

80. ## chemistry

Deterioration of buildings, bridges, and other structures through the rusting of iron costs millions of dollars everyday. Although the actual process also requires water, a simplified equation (with rust shown as iron(III) oxide (Fe2O3) is: 4Fe(s)+3O2(g)

81. ## Chemistry

Consider the combustion of propane: C3H8 + 5CO2 -> 3CO2 + 2H20. Delta H = -2221 kJ. What mass of propane must be burned to furnish this amount of energy assuming the heat transfer process is 60.% efficient?

82. ## Chemistry

Stoichiometry-I have the basic strategy, but am still stuck on how to do them.example...propane burns in oxygen according to the following reaction C3H8 + O2 produces CO2 + H20 a. How many moles of CO2 are formed when 2.8 g of propane reacts? b. If 0.45 g

83. ## chemistry

A propane barbeque is used to heat up 400g of water in an aluminum pot until it is boiling. Using the following information, calculate the molar enthalpy of propane. You can assume the temperature of the water and the temperature of the aluminum pot are

84. ## chemistry

A calorimeter consists of an interior metal bomb (container) surrounded by 2.22 kg of water all contained within an insulated exterior wall. A sample of propane, C3H8, weighing 6.89g, was burned in the calorimeter with excess oxygen. As a result of the

85. ## Chemistry

A 100 g piece of ice (solid water) at 0 °C melted to liquid water at 75.5 °C. If all the heat came from propane (C3H8) combustion, how many grams of propane Molar mass is 44.1'

86. ## Chem

A chemical reaction in a bomb calormeter evolves 4.66Kj of heat. If the heat capcity of the calorimeter is 1.38 Kj/C what is the temperature change?

87. ## chemistry

1. Heat can initiate reaction as well as be a product of chemical reactions. Cite the specific sample from the experiment that show heat acting in the manner.

88. ## Science at National University OF Samoa

2-bromobutane heat with 2M NaOH. What is the observation and the chemical reaction for the reaction?

89. ## chemistry -------------chemistry

If a flame on the candle burns red , how does energy of that flame compare to that of the Bunsen burner flame ? and why ? ans:The Bunsen burner flame has higher temperature than candle’s flame . Because flame of candle emit red ,and red has the least

90. ## Chemistry

Hii! I have a question: So the flame photometer uses a natural gas flame (1800 oC), what if it uses acetylene - nitrous oxide flame which is ~3000 oC, what would happen to the emission intensities? Thanks!

91. ## Chemistry

The combustion reaction of Mg +1/2 O2-->MgO produces a very bright white flame and high heat. Verify that the following reactions produce the same overall reaction: a) MgO+2HCl-->MgCl2+H2O b) Mg+2HCl-->MgCl2+H2 c) H2+1/2O2-->H2O ΔH°= -285.8 KJ/mol

92. ## Flame Colors - Chemistry

I've searched the internet but I can't find out what color flame a Nickel (or even better NiSO_4) solution will produce when burned. As well, does Aluminum (Al(SO_4)_3 ) have a flame color from the flame test? Don't know sorry!Wih I could help!Can you help

93. ## science

I put a peice of copper into a flame and I need to write a word equation for it. Whats a flame made up of cause I wanna write copper + _____ -> _______ + ________ I know its a synthesis reaction.

94. ## Chemistry

The combustion of 132 g of propane, C3H8, with excess oxygen liberates 6.6x10^3 kj of heat. What is the enthalpy change for the reaction below: C3H8(g) + 5O2(g) -> 3CO2(g) + 4H2O(l)

95. ## Chemistry

Complete the following chemical reaction. Label any precipitate that forms. KCl(aq) + AgNO3 (aq) ¨KNO3 (aq)+AgCl(s)

96. ## Chemistry

Is this the right way to write the structual and the chemical formula for propane? P P P P P C C C C P P P P P Pretend that there are bonds in between each of the letters. Chemical Formula: C3P8. Thanks for checking this out.

97. ## Chemistry

A calorimeter, with calorimeter constant 7.31 J K–1, was used to measure the heat of reaction for mixing 100.0 mL of 0.100 M Ag+ with 100.0 mL of 0.100 M Cl–. The temperature change was +0.770 K for the 200.0 g of solution (specific heat capacity =

98. ## chemistry

Which of the following minor products could not arise from the halogenation reaction below? a)2,5 dimethylhexane b)2 bromo-2 methyl propane c)1,3 dibromo, 2 methyl propane d) 2,4 dimethylhexane e)2,2,5 trimethyl pentane plz can someone help me...i kno its

99. ## organic chemistry

Which of the following minor products could not arise from the halogenation reaction below? isobutane + Br2 ----> 1-bromo-2-methyl propane + HBr + minor products a)2,5 dimethylhexane b)2 bromo-2 methyl propane c)1,3 dibromo, 2 methyl propane d) 2,4

100. ## Chemistry

I'm doing a flame testing lab in which I'm supposed to be able to identify an unknown element by observing the color it emits once heated. The color of the flame after heating this unknown metal is a light pinkish-violet. The question I need to answer asks