Chemistry

A hydrogen fuel cell is an electrochemical reactor in which oxygen and hydrogen gas are reacted to produce energy. Rather than combusting hydrogen in the presence of oxygen, the overall reaction (1/2) O2 H2 H2O is actually carried out as two `half-reactions occurring at separate electrodes. To complete the reaction, this forces electrons to pass through an external circuit from one electrode to the other, and this current can be used to do work; e.g., by driving a motor. Typical operating conditions for a solid-oxide fuel cell are 500-900 C and 5-15 bar. Consider a fuel cell in which a pure oxygen stream and a pure hydrogen stream enter at 11 bar and 700 C with stoichiometric flowrates. Assume that these reactants are consumed completely, and that the water generated by the reaction leaves in a third stream at the same T and P. Assume that the fuel cell operates at steady-state with a uniform temperature of 700 C. a) Write simplified first and
1 Answer
Select the correct answer.John is riding a ski lift to the top of Wildcat Mountain. He removes his gloves and rapidly rubs his hands together to warm them up. Whathappens when John rubs his hands?O A. The skin on his hands rapidly conducts heat, similar to metal.O B. He traps heat between his hands because skin is an insulator. ISO C. The particles In his hands vibrate faster because of friction.O D. Thermal energy moves from his fingertips to his palms.O E. He simulates a fever that'll raise his core body temperature.
2 Answers
b) Name three substances which can undergo sublimation and deposition respectively
1 Answer
Which of the following is a factor in natural selection?A. Individuals of species compete with one another to survive.B. Individuals better able to adapt to changes leave more offspring.C. All species are genetically diverse.D. All of the above.
2 Answers
What Mass of glucose is needed to prepare 235mL of 22% w/v glucose?
2 Answers
Select the correct answer.For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have? . .13.1426OD27O E40
1 Answer
a- Write the name of the process when the electron falls to a lower energy level and a photon is emitted
1 Answer
A student titrated 50 cm of sulphuric acid (H2SO4)of an unknown concentrationin a flask with sodium hydroxide (NaOH).The acid required 30 cm3 of 0.500 mol/dm3 NaOH to reach the end pointH2SO4(aq)+ 2NaOH(aq)Na2SO4(aq) + 2H2O()Calculate the concentration the acid.Concentration =mol/dm3
1 Answer
Plz help me!!!!plzzz!
1 Answer
Where is the arctic tundra biome found?Use this website to answer the question: https://thewildclassroom.com/biomes/artictundra-2/Question 2 options:Almost entirely in the Northern Hemisphere, from 60 to 70 degrees latitude North. In tropical and subtropical latitudesIn high altitudesWithin tropical and subtropical latitudes
2 Answers
Describe how urine is formed, beginning with the blood. In 5th grade language please
1 Answer
Which of the following is a period 4 representative element? A. C B. An C. Ti D. K
1 Answer
Draw a mechanism for the reaction of methanol with sodium amide. Draw any necessary curved arrows. Show the products of the reaction. Include any nonzero formal charges and all lone pairs of electrons. Finally, choose one of the options below to indicate which side of the reaction is favored at equilibrium.a) Reactants favoredb) Products favoredc) Neither side favored
1 Answer
What theoretical yield of NaCl would result from reacting 3.00 moles of Na2CO3 with excess HCl (aqueous)?
2 Answers
9If you wanted to make 250 mL of a 0.01 M solution of CaCl, calculate how many moles of calcium chloride would beneeded. Your response must include both a correct numerical setup and the calculated result. [1]
1 Answer
QUESTION 5Match the symbol with the type of symbiotic relationship it representssymbiotic relationships symbolA.Mutualism 1.+/+B.Commensalism 2.-/-C.Parasitism 3.+/0D.Competition 4.+/-
1 Answer
PLSSS ANSWERRRRR????
1 Answer
Determine how many molecules are in 86L of carbon dioxide at STP?
1 Answer
Describe Muller's Ratchet.
2 Answers
what color does blue and cyan pigment make?
2 Answers
Please someone help Im really confused
1 Answer
Water decomposes to hydrogen and oxygen gas as shown inthe following reaction:2H20 (g) 2H2 (g) + O2 (g)Given a 6.80 g sample of H20 (MM = 18.0 g/mol), how manygrams of oxygen (MM = 32.0 g/mol) is produced, assuming thedecomposition goes to completion?
1 Answer
Ca and F what are the name of the ionic compounds
1 Answer
You have 2.2 mol Xe and 2.1 mol F2, but when you carry out thereaction you end up with only 0.25 mol XeFg. What is the percentyield of this experiment?Xe(g) + 2 F2 (g) XeF, (g)
1 Answer