13.4 billion years is 3 times of the half-life, 4.47 billion years. So the Uranium-238 will go through three times of half decay. So the remain percentage will be 50%*50%*50%=12.5%.
Mole=number of molecules/6.02x10²³
mole=2
number of molecules= 2x6.02x10²³
number of molecules=12.04x10²³
The full sentences are given below:
1. During the process of erosion and deposition, sediments that are the SMALLEST in size will be carried the greatest distance before being deposited.
Erosion and deposition are the methods by which sand and rock particles are moved from one place to another. The erosion can be caused by water or wind. Water and wind have the capacity to transport particle from one location and deposit them in another location. How far the erosion is able to move the particles depend on the weight of the particles. It is easier for erosion to carry small particles over a long distance than for it to carry large particles over the same distance.
2. Most METAMORPHIC rocks form under conditions found a few kilometer under the earth surface.
Metamorphic rocks generally are formed from existing rocks. The existing rocks are usually subjected to heat and pressure, which cause radical changes in the chemical and physical properties of the rock. Metamorphic rocks can be formed underneath the earth surface if they are subjected to high temperature and pressure by the rock layers above them.
The two main types of chemical bonds are ionic and covalent bonds. An ionic bond essentially donates an electron to the other atom participating in the bond, while electrons in a covalent bond are shared equally between the atoms. The only pure covalent bonds occur between identical atoms.
