Answer:
you can classify a mineral by its appearance and other properties. The presence of a mineral is defined by the color and luster, and the color of the powdered mineral is described by the band. Every mineral has a distinctive density. To compare the hardness of rocks, the Mohs Hardness Scale is used.
Explanation:
Answer: Ammonium, when heated with aqueous base, will give off NH3 (ammonia) gas, (and depending, water vapor). This will leave the Cr2O3(s). From then on,
it is just adding or subtraction of gases or water vapor. You probably heard “Loss of electrons is Oxidation”, “Gain of Electrons is reduction”. That should help.
Explanation: This isn’t an explanation but an interesting point; Acid-Base and RedOx reactions are useful to the most complex of any Chemistry. Get this down, and Organic Chemistry will be much easier.
Answer: ice is less dense than liquid water. If ice was more dense, Earth would freeze.
Explanation: There are many reasons why life on Earth depends on the characteristics of water. One could discuss hydrogen bonds and its role as a solvent, but the unusual property of water is is the change in density with change in temperature. Water is densest at 4 degC, which is why ice floats - it is less dense than cold water (it melts quickly in warm water, so density isn’t impotant at higher temperatures). Most liquids are less dense than the solid, frozen form. If this was the case with water, any ice that formed would sink, and sease would freeze from the bottom up. Furthermore, the lowest layers would be insulated and would not all melt in summer. Thus over time, the seas would become a thin layer of liquid water at best, over solid ice. Life could not develop without liquid seas. In addition, ice is reflective, reducing the amount of sunlight absorbed, further reducing temperatures. Without ocean circulation, polar areas would be even colder, and there would be no rain.
The climate would become colder...
Answer:
For your first question, Curium does not occur naturally on Earth, meaning that it is not produced naturally on Earth. However, it can be formed in nuclear reactors.
For your second question, Curium has been used to provide power to electrical equipment used on space missions, but doesn't seem to be that important overall.
Explanation:
Hope this helped!