The correct answer is option a, that is, they produce ions when dissolved in water.
The acids and bases refer to the chemical components, which reacts with water. The molecules of acids dissociate to give hydrogen ions to water, while the bases dissociate to provide hydroxide ions to the water, or that takes hydrogen ions from water and leave the hydroxide ions behind.
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:
Burning is a chemical process by which two atoms or molecules will combine with each other. In burning, the two atoms or molecules will combine and release energy.When the molecules combine and release energy, it is released in the form of heat and often light.Different compounds react with oxygen differently – some contain lots of heat energy while others produce a smaller amount.The bigger the fuel load, the more intense the fire will be in terms of heat energy output. Moisture content: If the fuel isn't dry enough, it won't burn.Flames consist primarily of carbon dioxide, water vapor, oxygen and nitrogen. If hot enough, the gases may become ionized to produce plasma. Depending on the substances alight, and any impurities outside, the color of the flame and the fire's intensity will be different.