Answer: Between 8 and 14
Explanation: Ammonia is an inorganic compound of formula NH₃. Also known as ammonium hydroxide, it behaves as a weak base.
pHydrion paper is a chemical test indicator, i.e., it indicates the pH of a substance.
If inserted in Ammonia, pHydrion will indicate a range of 8 to 14 because in pH scale, indication of base is over 8 and up to 14. The exact number depends on the hydrogen ion concentration of the substance.
Answer:
D. Discovered chemolithotrophs in natural enviroments.
Explanation:
Sergei Winogradsky was a russian microbiologist. He observed in his research with genus of bacteria <em>Beggiatoa, </em>they were able to oxidize hydrogen sulfide as an energy source. Being the first example known of lithotrophs (organisms that use inorganic substrate in order to obtain energy).
The four limitations are
1.It's often impossible to repeat trials on the same subjects.
2-Subjects may report an inaccurate medical history.
3-It can be difficult to control all possible variables.
4-It's impossible to come up with testable scientific questions for human subjects.
Research involving human beings is ultimately necessary for improvements in human health and welfare. Any results about healthy physiology, illness causes, treatment effectiveness, learning, or behavior must be verified by carefully controlled investigations involving human participants. Sadly, not all human research have been valid and beneficial. It is possible to harm people in the name of research. The most well-known instances happened in Nazi Germany. Investigations conducted after the war found several crimes, including experiments in which participants were submerged in extremely cold water to determine how long it would take them to pass away from hypothermia.
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