Answer:
CFC’s illustrate that technical advances can be a “double-edged” sword as CFC's were made for the advantages but soon or later it came as a disadvantage for environment.
CFC's was discovered with many advantages such as they are stable, non-corrosive, and replacement of harmful ammonia used in refrigerators and air conditioning systems. But soon it is also discovered that CFC's are destroying the upper atmosphere layer called ozone, which is a very big disadvantage for us. CFCs are major contributor to global warming after carbon dioxide.
Hence, it proves that CFC’s shows how technological advancement can be “double-edged” sword.
Answer:
A flame test could help by seeing what things it could catch on fire from or the things that could happen with acids etc. I would test the medicine by asking someone who has had it in their life, asking doctors or I would maybe use it myself maybe. (I don’t know about c, sooo sorry)
B, because water is changing its state from solid to liquid (it's fusion in portuguese, don't know in english), so while it's changing, water has 2 states at the same time.
Are you sure you copied that down correctly? I know what NH3 is but HJ I am comming up blank on. The only thing HJ I know is hebdojoule which is unit system.
Are you doing chemical balancing?
I think the correct answer from the choices listed above is option B. <span>Of its 6 electrons, 4 are valence electrons, a carbon atom can form 4 covalent bonds with other elements. It is the 4 valence electrons available that allows this.
Hope this answers the question.</span>
