Number of atoms : 1.26 x 10²³
<h3>Further explanation </h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
0.21 moles of Al, so n = 0.21
Number of atoms :

Answer:
Einstein proposed that electromagnetic radiation has a wave-particle nature, that the energy of a quantum, or photon, depends on the frequency of the radiation, and that the energy of the photon is given by the formula Ephoton=hv.
Answer:
Energy of Movement.
Explanation:
Particles in a water wave exchange kinetic energy for potential energy When particles in water become part of a wave, they start to move up or down. This means that kinetic energy (energy of movement) has been transferred to them.
Answer: kindly check explanation
Explanation:
Given the following :
Measured density of copper block:
8.6+/-0.2 g/cm3
True density = 8.96g/cm3
Standard deviation = 0.4g/cm
a. What is the high and low number of the confidence interval range?
High : 8.6 + 0.2 g/cm3 = 8.8g/cm³
Low : 8.6 - 0.2 g/cm3 = 8.4g/cm³
Does the true value fall within the confidence interval? NO
Actual density = 8.96g/cm³ doses not lie in between (8.4 - 8.8)g/cm³
B.) High and low of the standard deviation range?
High = 8.6 + 0.4 = 9.0g/cm³
Low = 8.6 - 0.4 = 8.2g/cm³
Value falls within range of the true density value of copper block.
8.96g/cm³ falls in-between (8.2-9.0)g/cm³