Answer: A. Liquefy hydrogen under pressure and store it much as we do with liquefied natural gas today.
Explanation:
Current Hydrogen storage methods fall into one of two technologies;
- <em>physical storage</em> where compressed hydrogen gas is stored under pressure or as a liquid; and
- <em>chemical storage</em>, where the hydrogen is bonded with another material to form a hydride and released through a chemical reaction.
Physical storage solutions are commonly used technologies but are problematic when looking at using hydrogen to fuel vehicles. Compressed hydrogen gas needs to be stored under high pressure and requires large and heavy tanks. Also, liquid hydrogen boils at -253°C (-423°F) so it needs to be stored cryogenically with heavy insulation and actually contains less hydrogen compared with the same volume of gasoline.
Chemical storage methods allow hydrogen to be stored at much lower pressures and offer high storage performance due to the strong binding of hydrogen and the high storage densities. They also occupy relatively smaller spaces than either compressed hydrogen gas or liquified hydrogen. A large number of chemical storage systems are under investigation, which involve hydrolysis reactions, hydrogenation/dehydrogenation reactions, ammonia borane and other boron hydrides, ammonia, and alane etc.
Other practical storage methods being researched that focuses on storing hydrogen as a lightweight, compact energy carrier for mobile applications include;
- Nanostructured metal hydrides
- Liquid organic hydrogen carriers (LOHC)
The results of this experiment gave Rutherford the means to arrive at two conclusions: one<span>, an atom was much more than just empty space and scattered electrons and </span>two<span>, an atom must have a positively charged center that contains most of its mass (which Rutherford termed as the </span>nucleus<span>).
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Answer:
c) No, because Celsius is not an absolute temperature scale
Explanation:
converting 5 oC to kelvin which is the absolute temperature scale gives = 273 + 5 = 278 K
and converting 20 oC to kelvin = 20 + 273 = 293 K
the ratio = 278 / 293 = 0.94 approx 1 not 4
Answer:
less than 4.62 g
Explanation:
Sodium chloride contains 39% sodium by mass. Hence, 1 g of sodium chloride will contain:
39/100 x 1 = 0.39 g of sodium.
<em>If 1 g of sodium chloride contains 0.39 g of sodium, then how many g of sodium chloride will contain the 1.8 g required sodium per day?</em>
1 g sodium chloride = 0.39 g sodium
x g sodium chloride = 1.8 g sodium
x = 1.8 x 1/0.39 = 4.62 g of sodium chloride
<u>Since the adult is supposed to consume less than 1.8 g of sodium per day, the mass of sodium that should be consume per day and still be within the FDA guidelines will be less than 4.62 g of sodium chloride.</u>