Answer:
It is true that earth was once covered with oceans and little dry land.
Explanation:
Over the course of around four billion years, the Earth's oceans have lost about a quarter of their original mass. Today the atmosphere is rich in oxygen, which reacts with both hydrogen and deuterium to recreate water, which falls back to the Earth's surface. So the vast bulk of the water on Earth is held in a closed system that prevents the planet from gradually drying out. According to the researchers, the continents emerged relatively suddenly from an ocean that covered 95 percent of the Earth's surface. The appearance of large masses of dry land would have caused more extreme weather, changes in ocean currents and the emergence of proper seasons. In turn, these environmental changes may have led to rise in atmospheric oxygen that enabled the explosion of new life forms around 500 million years ago.
The answer is: hydrogen peroxide, H2O2.
H₂O₂(hydrogen peroxide) is pale blue, clear, inorganic liquid.
It is liquid because hydrogen bonds between molecules.
Hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom (H), covalently bound to a highly electronegative atom such as flourine (F), oxygen (O) and nitrogen (N) atoms.
Because of hydrogen bonds, hydrogen peroxide has higher melting and boiling temperatures than other molecules.
First, find moles of gold given the mass of the sample:
(35.9g Au)/(197.0g/mol Au) = 0.182mol Au
Second, multiply moles of Au by Avogrado's number:
(0.182mol)(6.02 x10^23)= 1.10x10^23 atoms Au
Answer:
The answer to your question is letter D. 2.02 g
Explanation:
Data
moles of Ne = 0.100
atomic mass of Neon = 20.18 g
Process
1.- Use proportions to find the answer
20.18 g of Ne ------------------ 1 mol of Ne
x ------------------ 0.1 moles
x = (0.1 x 20.18)/1
x = 2.018
2.- Consider the significant figures
0.100 has three significant figures so the answer must be 2.02 g
