10 most difficult chemistry riddlesChemistry quiz
Which has more calories: table sugar or aspartame?
pretty much the same
table sugar has much more calories
aspartame has much more calories
aspartame has no calories at all
Aspartame produces 4 kilocalories of energy per gram when metabolized, sucrose (table sugar) produces 3.9 kilocalories. However, aspartame is approximately 200 times sweeter than sucrose, so it is consumed in much smaller doses.
What does synthesis gas (water gas) consist of?
oxygen (O2) and hydrogen (H2)
methane (CH4) and water (H2O)
carbon dioxide (CO2) and hydrogen (H2)
carbon monoxide (CO) and hydrogen (H2)
Water gas is a mixture of carbon monoxide and hydrogen produced from synthesis gas. Synthesis gas is a useful product, but requires careful handling due to its flammability and the risk of carbon monoxide poisoning. The water-gas shift reaction can be used to reduce the carbon monoxide while producing additional hydrogen, resulting in water gas.
What is exactly the pH value of distilled water?
It depends on the temperature
Pure water is about 7 at 25 °C; this value decreases with increasing temperatures. At 50 °C, it is 6.55. It is also worth to note, that water that has been exposed to air is mildly acidic, because it absorbs carbon dioxide from the air.
What is the name of the most radioactive isotope on the planet?
210Po is extremely toxic, with one microgram being enough to kill the average adult (250,000 times more toxic than hydrogen cyanide by weight). 210Po was used to kill Russian dissident and ex-FSB officer Alexander V. Litvinenko in 2006.
Why is White Sands Desert in New Mexico so purely white?
it is gypsum
it is very fine grained sand
it iswhite quartz
it is an optical illusion
White Sands, having 442 total square kilometers of dune fields, is the world's largest surface deposit of gypsum. Unlike other desert sands, it is cool to the touch, due to the high rate of evaporation of surface moisture and the fact that the sands reflect, rather than absorb, the sun's rays.
Methanol (wood alcohol) is highly poisonous. Comparing to ethanol, is it more or less sedative?
that depends on the temperature
Methanol has a much weaker sedative effect than ethanol, which leads the victim to drink more than it would normally do with ethanol. Methanol is oxidized to formaldehyde and then to the poisonous formic acid in the liver.
What is the third by volume, after nitrogen and oxygen, component of dry air?
Argon makes up 0.934% of the earth's atmosphere. It is more than twice as abundant as water vapor and 23 times as abundant as carbon dioxide.
What is the name of an organic chemical compound used to treat alcoholism?
Disulfiram (sold under the trade names Antabuse and Antabus) is a drug used to support the treatment of chronic alcoholism by producing an acute sensitivity to ethanol (drinking alcohol).
What was included in the original Pepsi-Cola recipe?
coke from coal
Pepsi Cola, first introduced in 1898, was named after pepsin (enzyme) and kola (nuts). In 1931, the company entered bankruptcy and changed hands. The new owners changed the recipe to resemble more Coca-Cola.