The temperature of the globe has been ever increasing over the past 4 decades. We have also seen the rise of deforestation and etc. However, we have also seen advances in scientific technology that solves many complications. A very increasing field would be genetic modification or crispr and biomedical. Technology is also ever advancing into shaping the way we use gadgets. Internet access is no longer considered a privilege but a necessities to drive the economies running and keeping the nation economically stable. Many nations are now also heavily investing in space technologies for expedition to planet mars for the search of living things. In the past decades, renowned cosmologist Stephen Hawking has released many publications relating to Black holes etc. He had also went to talk about the existence of aliens and extraterrestial lifeforms and how the world may come to the end because of aliens. This is not a exhaustive lists of the events happened over the past 4 decades but it gives you brief through about the many contributions that the scientific community has given. Thus, this is all.
Answer:
0.12 M hydrofluoric acid + 0.17 M potassium fluoride
Explanation:
To make a buffer, you must to have an aqueous mixture of a weak acid and its conjugate base or vice versa.
Knowing that:
0.32 M calcium chloride + 0.27 M sodium chloride: <em>is not a good buffer system </em>because CaCl₂ and NaCl are both salts.
0.35 M ammonia + 0.36 M calcium hydroxide <em>is not a good buffer system </em>because ammonia is a weak base but calcium hydroxide is a strong base
0.19 M barium hydroxide + 0.28 M barium chloride <em>is not a good buffer system </em>because Ba(OH)₂ is a strong base.
0.12 M hydrofluoric acid + 0.17 M potassium fluoride <em>is a good buffer system </em>because HF is a weak acid and KF (F⁻ in aqueous medium), is its conjugate base
0.20 M hydrobromic acid + 0.22 M sodium bromide <em>is not a good buffer system </em>because HBr is a strong acid.
Answer:
Igneous rocks do not contain any fossils.
Explanation:
This is because any fossils in the original rock will have melted when the rock melted to form magma. Sedimentary rocks are formed from the broken remains of other rocks that become joined together.
