Answer:
A cation has more protons than electrons, consequently giving it a net positive charge.
Answer:
Metallic bonding is found in metals and their alloys. When the atoms give up their valence electrons, they form ions. These ions are held together by the electron cloud surrounding them. Metals are shiny because they have a lot of free (i.e. delocalized) electrons that form a cloud of highly mobile negatively charged electrons on and beneath the smooth metal surface in the ideal case. ... In the absence of any external EM field, the charges in the plasma are uniformly distributed within the metal.
Explanation:
In metallic bonding, the electrons are “surrendered” to a common pool and become shared by all the atoms in the solid metal.
Answer:
9000 BC
Explanation:
Although various copper tools and decorative items dating back as early as 9000 BCE have been discovered, archaeological evidence suggests that it was the early Mesopotamians who, around 5000 to 6000 years ago, were the first to fully harness the ability to extract and work with copper.
The correct matches are:
1. Exosphere - Temperatures reach as high as 2000 C yet it feels very cold
This is the top layer of the atmosphere. The atoms are so dispersed that despite it having very high temperature it doesn't feel like it at all.
2. Thermosphere - Particles that have enough energy can escape into space
The thermosphere is the fourth highest layer of the atmosphere. The atoms in this layer are relatively distant from one another, so the particles that have enough energy manage to escape easily into the exosphere and then the space.
3. Mesosphere - It is the coldest region of the atmosphere
The mesosphere is the third highest layer. In this layer the temperatures constantly drop, and they go down to -85 degrees, making it the coldest layer by far.
4. Stratosphere - Ninety percent ozone is in this layer
The startosphere has a separte zone in it which is dominated by only one gas, the ozone. It is called the ozone layer, the one that protects the Earth from too intense UV radiation, and in fact over 90% of this gas is locate here.
5. Troposphere - It is warm due to the heat from Earth's surface
The troposphere is the densest and lowest of the layers. It is the one that also has Greenhouse gases which manage to trap the heat that is radiated from the surface of the Earth, thus keeping this layer relatively warm.
Answer:
I think it would be the last answer
Explanation:
