Answer:
Explanation:
not sure if this is totally correct but checked with classmates and this seems to be around what most got
Answer:
It's funny cause i'm doing the same exact thing as you.
Explanation:
You need to go to the Gizmo, and it explains everything. But When you're looking at "Valence Electrons" thats how many "dots" (electrons) there are on the outermost circle, so Fluorine has 7 Valence Electrons. To find the valency, you need to first identify the Valence Electrons. Fluorine has 7 valence electrons, and it would be a lot easier for this atom to gain an electron, rather than lose 7. So 8-7 is 1, meaning the Valency of Fluorine will be 1. For the sum, just add the total number, so 7+1 is 8, so the sum of Fluorine will be 8. This is confusing, so I'm sorry if this doesn't make sense.
Answer: 238.6 J
Explanation:
1) Chemical energy is indicated as enthalpy
2) Energy balance:
∑ enthalpy of the reactants + energy added = ∑ enthalpy of the products + energy released.
3) ∑ enthalpy of the reactants = 85.1 J + 87.9 J = 173 J
4) energy added = 104.3 J
5) ∑ enthalpy of the products = 38.7 J + D
6) energy released = 0
7) Equation:
173J + 104.3J = 38.7 + D + 0
⇒ D = 173J + 104.3J - 38.7J = 238.6J, which is the chemical energy of the product D.
Answer:238.6 J
Explanation:
Answer:
The correct answer is "Oxidation at the anode and reduction at the cathode".
Explanation:
A rechargeable battery is recharged by the movement of electrons from an external power source into the battery. In order to achieve this, two process take place inside the rechargeable battery: oxidation at the anode and reduction at the cathode. The electrons flow within the battery from the anode to the cathode, this happens by the oxidation of the anode (loss of electrons) and the reduction at the cathode (gain of electrons).
Answer:
I think robots would be better. Even though it might take time or take a lot of money to make the robots, it is safer than sending humans into space. Also, if we were to send a ship somewhere far away in our solar system or even past it, it would be hard for humans, and they may not even survive long enough to get there. Robots, however, can survive longer, and, since they are programmed by humans, we can program them to record the data in space, and they can constantly record space as they travel. We also would be risking less lives, and wouldn't be putting too many risks on the survival of the humans sent into space. The only downside would be that the robots can malfunction, but other than that, robots are better. :)
Answer:
The National Aeronautics and Space Administration has a difficult task. It must convince U.S. taxpayers that space science is worth $16.25 billion a year. To achieve this goal, the agency conducts an extensive public-relations effort that is similar to the marketing campaigns of America's biggest corporations. NASA has learned a valuable lesson about marketing in the 21st century: to promote its programs, it must provide entertaining visuals and stories with compelling human characters. For this reason, NASA issues a steady stream of press releases and images from its human spaceflight program
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The space agency is now saddled with the International Space Station, the budget-hemorrhaging “laboratory” orbiting Earth. NASA says the station provides a platform for space research and helps to determine how people can live and work safely in space. This knowledge could be used to plan a manned mission to Mars or the construction of a base on the moon. But these justifications for the station are largely myths. Here are the facts, plain as potatoes: The International Space Station is not a platform for cutting-edge science. Unmanned probes can explore Mars and other planets more cheaply and effectively than manned missions can. And a moon colony would be a silly destiny.
The Myth of Science
IN 1990 THE American Physical Society, an organization of 41,000 physicists, reviewed the experiments then planned for the International Space Station. Many of the studies involved examining materials and fluid mechanics in the station's microgravity environment. Other proposed experiments focused on growing protein crystals and cell cultures on the station. The physical society concluded, however, that these experiments would not provide enough useful scientific knowledge to justify building the station. Thirteen other scientific organizations, including the American Chemical Society and the American Crystallographic Association, drew the same conclusion.
Since then, the station has been redesigned and the list of planned experiments has changed, but the research community remains overwhelmingly opposed. To date, at least 20 scientific organizations from around the world have determined that the space station experiments in their respective fields are a waste of time and money. All these groups have recommended that space science should instead be done through robotic and telescopic missions.
These scientists have various reasons for their disapproval. For researchers in materials science, the station is simply too unstable a platform. Vibrations caused by the movements of astronauts and machinery jar sensitive experiments. The same vibrations make it difficult for astronomers to observe the heavens and for geologists and climatologists to study Earth's surface as well as they could with unmanned satellites. The cloud of gases vented from the station interferes with experiments in space nearby that require near-vacuum conditions. And last, the station orbits only 400 kilometers (250 miles) overhead, traveling through a region of space that has already been studied extensively.
Despite the scientific community's disapproval, NASA went ahead with experiments on the space station. The agency has been particularly enthusiastic about studying the growth of protein crystals in microgravity; NASA claims the studies may spur the development of better medicines. But the American Society for Cell Biology has bluntly called for the cancellation of the crystallography program. The society's review panel concluded that the proposed experiments were not likely to make any serious contributions to the knowledge of protein structure.
ADVERTISEMENT The Myth of Economic Benefit
HUMAN SPACELIGHT is extremely expensive. A single flight of the space shuttle costs about $450 million. The shuttle's cargo bay can carry up to 23,000 kilograms (51,000 pounds) of payload into orbit and can return 14,500 kilograms back to Earth. Suppose that NASA loaded up the shuttle's cargo bay with confetti before launching it into space. Even if every kilogram of confetti miraculously turned into a kilogram of gold during the trip, the mission would still lose $80 million.
The same miserable economics hold for the International Space Station. Over its history the station underwent five major redesigns and fell 11 years behind schedule. NASA has spent over three times the $8 billion that the original project was supposed to cost in its entirety.
NASA had hoped that space-based manufacturing on the station would offset some of this expense. In theory, the microgravity environment could allow the production of certain pharmaceuticals and semiconductors that would have advantages over similar products made on Earth. But the high price of sending anything to the station has dissuaded most companies from even exploring the idea.
OP already did it - CONGRATS!!
here are the steps 2 get the same ans:
(NH4)2 CO3 has 2x N, 8x H, 1x C and 3x O per molecule
so its molecular mass = 2x14 + 8x1 + 1x12 + 3x16
=28+8+12+48
=96g
of that 96g, 8x1=8g is due to Hydrogen
so by ratio n proportion, 1.00g will have 1x8/96 = 1/12g = 0.083g of H