Answer: It was known as the SPACE RACE.
Explanation: The space race was a cold war between the Soviet Union (USSR) and the United States (US), to get satellites and humans into space. The competition began in earnest on August 2, 1955, when the Soviet Union responded to the US announcement. On April 12, 1961, the USSR surprised the world again by launching Yuri Gagarin into a single orbit around the Earth in a craft they called Vostok 1.
scandium. if you look up the number of electrons thats the periodic number and it gives you the answer
A. Air expands, becomes less dense and rises when the temperature is high due to the increased kinetic energy. This causes the air molecules to move around much more so they are further apart.
Answer:
d) V = 91.3 L
Explanation:
Given data:
Volume of nitrogen = ?
Temperature = standard = 273.15 K
Pressure = standard = 1 atm
Number of atoms of nitrogen = 2.454×10²⁴ atoms
Solution:
First of all we will calculate the number of moles of nitrogen by using Avogadro number.
1 mole = 6.022×10²³ atoms
2.454×10²⁴ atoms × 1 mol / 6.022×10²³ atoms
0.407×10¹ mol
4.07 mol
Volume of nitrogen:
PV = nRT
1 atm × V = 4.07 mol ×0.0821 atm.L /mol.K ×273.15 K
V = 91.3 atm.L /1 atm
V = 91.3 L
Answer:
The edge length of a face-centered cubic unit cell is 435.6 pm.
Explanation:
In a face-centered cubic unit cell, each of the eight corners is occupied by one atom and each of the six faces is occupied by a single atom.
Hence, the number of atoms in an FCC unit cell is:
In a face-centered cubic unit cell, to find the edge length we need to use Pythagorean Theorem:
(1)
Where:
a: is the edge length
R: is the radius of each atom = 154 pm
By solving equation (1) for "a" we have:
Therefore, the edge length of a face-centered cubic unit cell is 435.6 pm.
I hope it helps you!
