The space shuttle uses fuel cells( AFC's) to produce electricity . In these fuel cells,O2 reacts with water and electrons to produce OH- ioins travel to the other electrode where they react with H2 to release electrons and produce more

71,172 results

Chemistry

The space shuttle uses fuel cells( AFC's) to produce electricity . In these fuel cells,O2 reacts with water and electrons to produce OH- ioins travel to the other electrode where they react with H2 to release electrons and produce more water. Based on this information,write (...

chemistry

Suppose a fuel-cell generator was used to produce electricity for a house. If each H2 molecule produces 2e- , how many kilograms of hydrogen would be required to generate the electricity needed for a typical house? Assume the home uses about 850 kWh of electricity per month, ...

Chemistry

Suppose a fuel-cell generator was used to produce electricity for a house. If each H2 molecule produces 2e- how many kilograms of hydrogen would be required to generate the electricity needed for a typical house? Assume the home uses about 850 kWh of electricity per month, ...

Chemistry

Suppose a fuel-cell generator was used to produce electricity for a house. If each H2 molecule produces 2e-, how many kilograms of hydrogen would be required to generate the electricity needed for a typical house? Assume the home uses about 850 kWh of electricity per month, ...

math

according to information from NASA, the space shuttle has a capacity of about 500,000 gallons of fuel. Write three numbers that could represent the space shuttle's actual fuel capacity? I don't understand the question.

phys

The space shuttle, with an initial mass M = 2.41E+6 kg, is launched from the surface of the earth with an initial net acceleration a = 26.1 m/s2. The rate of fuel consumption is R = 6.90E+3 kg/s. The shuttle reaches outer space with a velocity of vo = 4632 m/s, and a mass of ...

chem

can anyone help me with this question what is the advantages and disadvantages of hydrogen power as opposed to hydrogen fuel, also what is the equation for hydrogen feul? I do not understand your first question. Hydrogen power REQUIRES hydrogen fuel. Hydrogen fuel is H2; ...

Physics Help Please!!!!

During a launch of the shuttle, fuel is being burned at a rate of 2000 kg every second. the exhaust from the burning of this fuel is expelled by the engines and can be seen during the launch. readings from instruments mounted on the space shuttle show that for the first 2 min ...

chem

Suppose a hydrogen-oxygen fuel-cell generator was used to produce electricity for a house. Use the balanced redox reactions and the standard cell potential to predict the volume of hydrogen gas (at STP) required each month to generate the electricity needed for a typical house...

Exploring Space

if u could travel at the speed of ligt without fuel, where would the energy required for the engine come from? is this possible? it is impossible to travel anywhere without fuel. The only other option is to walk by foot. I don't know the answer to the question, i'm stumped, ...

Physics

The space shuttle, with an initial mass M = 2.41×106 kg, is launched from the surface of the earth with an initial net acceleration a = 26.1 m/s^2. The rate of fuel consumption is R = 6.90×103 kg/s. The shuttle reaches outer space with a velocity of vo = 4632. m/s, and a ...

Science

What happens when bacteria reproduce by binary fission? a. two cells produce a third cell. b. one cell produces two cells. c. one cell produces three or more cells. d. two cells produce two more cells.

Chemistry

Suppose a hydrogen-oxygen fuel-cell generator was used to produce electricity for a house. Use the balanced redox reactions and the standard cell potential to predict the volume of hydrogen gas (at STP) required each month to generate the electricity needed for a typical house...

science

what are cells made from? Please, what kind of cells? There are many kinds. Jail cells, hive cells, plant cells, animal cells, blood cells, brain cells. We need a more definitve question.

physics

the solid fuel rocket boosters used to launch the space shuttle are able to lift the shuttle 45 kilometers above earths surface. During the 2.00 min that the boosters operate, the shuttle accelerates from rest to a speed of nearly 7.50 x 10^2 m/s. What is the magnitude of the ...

Biology

After a strain of bacterial cells is exposed to a chemical mutagen, only 30% of the cells produce new colonies that continue to grow. Which of the following can be concluded? A. Some cells underwent advantageous mutations. B. Some cells underwent neutral mutations. C. Some ...

Biology - please help

After a strain of bacterial cells is exposed to a chemical mutagen, only 30% of the cells produce new colonies that continue to grow. Which of the following can be concluded? A. Some cells underwent advantageous mutations. B. Some cells underwent neutral mutations. C. Some ...

Science

A cell can no longer supply energy when it cannot provide a closed path for electrons and ions to travel. Based on your knowledge of cells and batteries, where can a cell fail? Provide 3 specific examples. Unfortunately, the only example I can think of is when the reactants ...

bio

T or F? stem cells in the bone marrow can produce more than a dozen types of blood cells, replacing those lost due to normal wear and tear. T or F? only eukaryotic cells undergo true mitosis.

MATH

I need help on number 3.the question is. According to information from NASA the space Shuttles external fuel tank has a capacity of about 500,000 gallons of fuel.Write three numbers that could represent the space Shuttles actual fuel capcity.

chemistry

Several things stand in the way of hydrogen fuel cells becoming widely used. Is it easy or difficult to store enough hydrogen to fuel a car? Is the technology expensive or cheap? Is the infrastructure present?

life science

Explanation of why the process of mitosis and meiosis are both important to a living organism. When would an organism need to undergo the process of mitosis? When would an organism need to undergo the process of meiosis? What would happen if meiosis did not occur I will gladly...

Physics

An engine of the orbital maneuvering system (OMS) on a space shuttle exerts a force of for 3.90 s, exhausting a negligible mass of fuel relative to the 95,000-kg mass of the shuttle. (a) What is the impulse of the force for this 3.90 s? (b) What is the shuttle’s change in ...

biology

All of the cells are in the very early stages of embryonic development and have not begun to differentiate into specialized types of cells. What type of cells would these be? A) gametes B) stem cells C) somatic cells D) epidermal cells

Chemistry

Which of these is more efficient on a large/small scale (power generation) and why? burning hydrogen to generate heat to drive turbines to produce electricity or directly producing electricity in a fuel cell reaction Can hydrogen be piped into homes, offices the way natural ...

Health (Ms. Sue)

Describe the role of white blood cells in developing immunity from pathogens. A: White blood cells produce antibodies that then bind to specific pathogens and warn other white blood cells to destroy the pathogens. Therefore, white blood cells play an immense role in developing...

science

"Reproductive cells and somatic cells are not separated early in development, as they are in animals。 Instead, plant somatic cells that have undergone many rounds of mitosis can undergo meiosis and produce gametes." This is said in my notes under properties of plants ...

Chemistry 2 Ap

The reusably booster rockets of the U.S space shuttle employ a mixture of aluminum and ammonium perchlorate for fuel. A possile equation for this reaction is 3Al+3NH4CLO4---> Al2O3+ AlCl+ 3NO+ 6H2O What mass of the NH4CLO4 should be used in the fuel mixture for every ...

biology

which of the following types of cells need to make energy to perform basic functions like growing, moving, and reproducing? -animal cells -animal cells and bacteria cells -animal cells, bacteria cells, and plant cells -plant cells

Biology

Are these correct? A. harvests energy from organic compounds= mitochondria B. makes proteins in both types of cells= ribosomes C. uses light energy to make food= chloroplasts D. outer support for plant cells= cell wall E. gives shape and protection to animals= cell membrane F...

Peinciples of Management

a 31 year old female contracted HIV human immunodeficiency syndrome) Ordinarily harmless infections are deadly to her. Which answer below best explains how her antibody-response (b cell immunity) became weakened even though HIV primarily infects cells involved in T cell ...

Science

Match these with the key terms (1) A form of energy that is always transferred from a warmer substance to a cooler one. (2) device that converts hear to a small amount of electric energy often used in temperature sensors. (3) A Push button barbecue lighter produces a small ...

Science

How many cell divisions would it take to produce at least 1,000 cells from one cell? (When one cell splits in half during cell division, the result is two new cells. Each of those cells can divide into two more and so on.) Answer (256?)

Biology

What do plants and algal cells need to produce proteins? Where do plants and again cells get this supple from? THANKS!!!

science

Choose one primary reference that uses cultured cells as an experimental model. Describe briefly the type of cells used, why these particular cells were useful for the study and how they are used. List two ways in which the cells used in the study would resemble cells that are...

Chemistry Balancing Equations

I really need help with balancing these equations: PLEASE HELP!! 1. Sodium Hydrogen Sulfite reacts with hydrochloric acid to produce sulfur dioxide gas, water and sodium chloride 2. Sodium nitrate reacts with hydrochloric acid to produce nitrogen monoxide gas, water sodium ...

Science

Describe the difference and function between how plant cells and animal cells obtain food. I put something like- plant cells get food by photosynthesis, using chloroplast, sun, water, and carbondioxide. animal cells get food by digesting water, meat, vegetables, nutriends, ...

Biology

Respond to this question: "If a plant doesn't have enough water to openits guard cells, how would this affect its rate of transpiration?" In your answer, discuss the following: - the guard cell's role in transpiration - what effect this would have on the stomata - how this ...

chemistry

Problem#9: Consider the fuel octane (the main component of gasoline) and its combustion reaction 2C8H18(l) + 25O2(g) → 16CO2(g) + 18H2O(l) ΔHo = -10,942 kJ The “fuel value” of a fuel (unit kJ/g) is defined as the energy released when 1 g of the fuel undergoes ...

Physics

The hoover dam produces 2x10 to the 9 W of electricity. It is composed of 7x10 to the 9 kg of concrete. To produce 1 kg of concrete requires 1 MJ of energy. How much energy did it take to produce the dam? How long was the "energy payback time" for the dam? The area of Lake ...

physics

What reaction would you get from francium and water in outer space and what if you added hydrogen to the experiment as far as being used for fuel for travel

Math

an airport mixes and additive into its jet fuel. The ration of fuel to additive needs to be kept the same. Complete the table below for amount of additive required for different amounts of fuel fuel (kg) 63 84 98 add 9(g) 30 42 48

science: cells

1~ What do red blood cells do and is there anything significantly different about them from other types of cells? 2~ What are bone cells and is there anything significantly different about them from other types of cells? (I just need help for studying i was absent a week from ...

Chemistry

One proposed design for a Mars rover uses a methane gas fuel cell as its power supply. The methane fuel can be made on Mars using a chemical reaction that has been known for over 100-a the Sabatier methanation reaction: C02(g) + 4H2(g)<--> CH4(g) +2H2O(g) Enthalpy change...

biology - cells

Which scientist proposed that cells come from other cells? A. Hooke B. van Leeuwenhoek C. Schwann D. Virchow

physics

Design an array of individual solar cells that woulproduce 120 volts DC. About how large an area of solar cells would be needed to produce 2 kWe of/ output power at noon on a clear day

Science

What means Cells in Science? It depends on the context: In electricity, or chemistry, cells are sources of electrical energy. In life science, cells are the basic unit of construction for animal or plant life.

help please physics

Design an array of individual solar cells that woulproduce 120 volts DC. About how large an area of solar cells would be needed to produce 2 kWe of/ output power at noon on a clear day

Science Plzz Help

2. Which of the following best describes the function of the endocrine system? A. It secretes chemical messengers that travel through the blood to signal changes at target cells. B. It binds chemical messengers that travel through the blood from target cells. C. It releases ...

science

the three fuel sources to make electricity are what coal, natural gas, fuel oil ure mom ure dad and ur brother Coal, natural gas and fuel oil

physics

I have no idea how to do this problem: Design an array of individual solar cells that woulproduce 120 volts DC. About how large an area of solar cells would be needed to produce 2 kWe of/ output power at noon on a clear day

math

Keo's model airplane uses 0.03L of fuel each minute it flies. If the fuel tank holds 0.5L,how long can the plane fly without refueling?

Sciencee

which of the following best describes the function of the endocrine system A. it secretes chemical messengers that travel through the blood to signal changes at target cells. B. It blinds chemical messengers that travel through the blood from target cells. C. It releases ...

Chemistry

Hydrogen gas is a very environmentally friendly fuel source. One factor that is important in determining whether it is used as a fuel source is the cost of production. Use the two equations below to evaluate which reaction requires more energy to produce 1 mol of ​H2(g). ...

Advanced Biology

The cells of cellular slime molds bear a resemblance to: a) flagellated cells b) diatoms c) ciliated cells d) dinoflagllates e) amoeboid cells I think it's b!

science

which of the following is not part of cell theory? A. cells are the building blocks of life B. all living things are made up of cells C. all cells are created from other cells though cell division<------------ D. The nucleus is the control center of the cell

Science

Which of the following is not part of the cell theory? A.Cells are the building blocks of life. B.All living things are made up of cells. C.All cells are created from other cells through cell division. D.The nucleus is the control center of the cell.***

chemistry - decomposition of water(help)

Hydrogen is a very appealing fuel, in part because burning it produces only non-polluting water. One of the challenges that researchers face in making hydrogen fuel a reality is how to produce hydrogen economically. Researchers are investigating methods of producing hydrogen ...

chemistry - decomposition of water(help)

Hydrogen is a very appealing fuel, in part because burning it produces only non-polluting water. One of the challenges that researchers face in making hydrogen fuel a reality is how to produce hydrogen economically. Researchers are investigating methods of producing hydrogen ...

Science

Which of the following is not part of the cell theory? Cells are the building blocks of life. All living things are made up of cells. All cells are created from other cells through cell division. (MY ANSWER) The nucleus is the control center of the cell.

chemistry

4)You count your cells and have 8x10ᶺ5 viable cells/ml you want to see (dilute the cells) to end up with 2x10ᶺ5 viable cells/ml. What volume of cells will you put into 20 ml?

Biology

4)You count your cells and have 8x10ᶺ5 viable cells/ml you want to see (dilute the cells) to end up with 2x10ᶺ5 viable cells/ml. What volume of cells will you put into 20 ml?

science

Which of the following is NOT a function of proteins? a: act as a main fuel for cells B: control chemical reactions in a cell

science

Which of the following is NOT a function of proteins? a: act as a main fuel for cells B: control chemical reactions in a cell

science

Which of the following is NOT a function of proteins? a: act as a main fuel for cells B: control chemical reactions in a cell

math

The fuel rods for a certain type of nuclear reactor are bundled into a cylindrical shell. Consider this cross-section showing 19 identical fuel rods: a) If the diameter of the cylindrical shell is 12.35 cm, calculate the shaded area of the cross-section. b) If the length of ...

Biology

name three ways somatic cells are different from gamete cells. 1. Gametes are sex cells and are always haploid 2. Somatic cells are non sex cells 3. ?

English

Sunlight hits the solar cells on the backpack. The solar cells change sunlight into electricity. The electricity is stored in the battery. A cell phone or an MP3 player can be plugged into it. (In this passage, what does 'it' refer to in the last sentence?)

Biology

The combustion of petrol in a car engine releases about as much energy per gramme of fuel as the repiration of sugar in cells. Try to explain, in outline, the fundamental differences between the processes I am taking Biolagy right now and i am having a hard time to. If you ...

Chemistry Balancing Equations

Can you please tell me if these are correct? 1. Sodium Hydrogen Sulfite reacts with hydrochloric acid to produce sulfur dioxide gas, water and sodium chloride NaHSO3 + HCl -----> SO2 + H2O + NaCl 2. Sodium nitrate reacts with hydrochloric acid to produce nitrogen monoxide ...

Health

The three lines of defense your body has against disease include all except? A. physical and chemical defenses B. inflammation C. immune system D. scarring True or false B cells and H cells are two important cells in the immune system that help fight infection. Antibodies are ...

Exploring Space

I need to know about the 3 conditions which are need necessarily to travel to the stars. My answer is below. Please add any other information, thanks. Not so sure if my answer makes sense. 3 conditions which are needed neccessarily to travel to the stars are a way to exceed ...

math

a car travels at a constants speed and uses G(x) litres of gas per kilomotre, where x is the speed of the car in kilomotres oer hour and G(x)=(1280+x^2)/(320x) a>if fuel costs 1.29 per litre, determine the cost function C(x)that expresses the cost of the fuel for a 200KM ...

health

2. ________ in the pancreatic islets secrete the hormone insulin in response to a high concentration of glucose in the blood. A. Beta cells B. Alpha cells C. Gamma cells D. Sigma cells i put b but it said it was wrong

Chemistry of Life

Which statement is true about water molecules? The oxygen atom has a negative charge. The hydrogen atoms do not share electrons. Water molecules move randomly around each other. Water molecules cannot dissolve many substances. Question 2. How does water relate to the ability ...

Biology

In plants, cells that transport water against the force of gravity are found to contain many more mitochondria than some other plant cells. What is the reason for this?

Chemistry

Suppose that you are planning a backpacking trip and will need to boil 40 L of water for your group. What volume of fuel should you bring? Assume each of the following: the fuel has an average formula of C7H16; 15% of the heat generated from combustion goes to heat the water (...

chemistry

Suppose that you are planning a backpacking trip and will need to boil 40 L of water for your group. What volume of fuel should you bring? Assume each of the following: the fuel has an average formula of C7H16; 15% of the heat generated from combustion goes to heat the water (...

chem

A hydrogen-oxygen fuel cell operates on the simple reaction given below. H2(g) + 1/2 O2(g) H2O(l) If the cell is designed to produce 1.8 A of current, and if the hydrogen is contained in a 2.9 L tank at 200. atm pressure at 25°C, how long can the fuel cell operate before the ...

Science

although electromagnetic waves differ in the wavelengths they all travel at the speed of light which is A.300,00km/s B.6000km/h c.100km/s d.10,00km/s A rocket is a motor that can urn fuel without requiring A.water B.air c.electricity d.fire

Physiology

Anesthetics such as ether, chloroform and nitrous oxide reduce responsiveness of cells by blocking ion channels and altering other properties of cells. What chemical property of these molecules enables them to easily enter cells?

biology

Cellular Respiration and Photosynthesis co-exist as paired metabolic processes. Photosynthesis uses light energy to convert carbon dioxide into glucose, a simple sugar, in two steps, the light dependent and light independent reactions. Oxygen is produced as a by product during...

Chemistry

As I read it, the question provides you with a word description of the production of diesel fuel, gasoline, lighter gases such as ethane and propane, as well as some of the refinery operations such as cracking. Your job is to take this word description and write an equation ...

Biology*STUCK*

A group of students was asked to list some of the similarities and differences between prokaryotic cells and eukaryotic cells. They created the table shown above. The students made a mistake in creating their table. Which statement best describes their mistake? a) Both ...

Physics

An electric catfish can generate a significant potential difference using stacks of special cells called electrocytes. Each electrocyte develops a potential difference of 110 mV. How many cells must be connected in series to give the 350V a large catfish can produce?

biology

how do some cells become brain cells and others become skin cells when the DNA in all of the cells is exactly the same

Are my answers correct? Chem

I really need help with balancing these equations: Can you check if my answer are correct? Please 1. Sodium Hydrogen Sulfite reacts with hydrochloric acid to produce sulfur dioxide gas, water and sodium chloride NaHSO3 + HCl = SO2 + H2O + NaCl 2. Sodium nitrate reacts with ...

8th-g Science: Need help to check answer!!!

Since I will have a science test next week based on these questions but my teacher won't check all answer with the class. I don't want to make a mistake and study to an incorrect answers. Do you mind to check the answers for me so that I am able to see if I got it correct or ...

chemistry

An intercontinental ballistic missile (ICBM) travels at an average speed of 7.03km/sec. The missile contains 459.0Mg of fuel. The fuel is burned at a rate of 313 pounds per second. What would be the maximum distance (in km) the missile could travel until it ran out of fuel? ...

Chem

Aviation fuel is significantly more expensive per gallon than diesel fuel. Why then is aviation fuel still used in Planes?

biology

How does mitosis in plant cells differ from that in animal cells? A. Animal cells lack a cell plate. B. Plant cells lack centrioles. C. Plant cells lack spindle fibers. D. Animal cells lack cytokinesis. I chose b but I got it wrong please help....

Health

1. What is needed to make blood cells? 2. What pair of workers is needed to produce estrogen? 3. What is needed to produce eleven hormones that control the actions of other endocrine glands? 4. What is needed to pass oxygen from lungs into blood vessels and welcome carbon ...

Chemistry

Okay so I'm doing an assignemtn and one of the questions has stumped me. It asks: The solid fuel booster rockets on the space shuttle employ a mixture of aluminium and ammonium perchlorate. The reaction is: 2Al(s) + 2NH4ClO4(s) → Al2O3(s) + 2NO(g) + 3H2O(g) + 2HCl(g) ...

algebra 1

Harold's car has a fuel tank with 12 gallons of fuel in it. The fuel efficiency of Harold's car is 25 miles per gallon. Write an equation to represent the amount of fuel remaining, f, in Harold's car after driving m miles.

science

chemical reaction in cells that needs oxygen to release energy and produce carbon dioxide and water as waste 1)breathing 2)exhaling c)inhaling d)respiration

Radiation therapy

In radiation therapy, a.isotopes are traced through a chemical reaction. b.unhealthy human cells are destroyed. c.radioactive isotopes are used as fuel. d.weak spots in water pipes are found. C?

Check please science

Cells are to tissues as organs are to 1 ORGAN SYSTEM 2 CELLS 3 GENES 4 ORGANELLES IS THE ANSWER 1 ORGAN SYSTEM Which of statements about cells is not true? 1. One or more cells make up all living organisms 2 cells carry on the basic life functions of living organisms 3 cells ...

physics

explain the close relationship between magnetism and electricity? and How can electricity produce magnetism, and magnetism produce electricity.

schwann cells

are they found in central nervous system are they found in peripheral nervous system do they form a myelin sheath do they increase the speed of propagation of nervous impulses Thank you for using the Jiskha Homework Help Forum. Here is a site with the definition and yes, they ...

Math

(Growth of Cells) Suppose that after t hrs, there are p (t) cells present in a culture, where P(t) = 5000e*^2t a) How many cells were present initially? b) Give a differential equation satisfied by P(t) c) When will the population double? d) When will 20,000 cells be present?

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