Answer:
1. The Nummber of electrons present in the outermost shell is called Valence electrons.
2. Thomson model:
Thomson model of atom is the model which states that electrons are embedded in a positively charged solid material which is spherical in shape.
Rutherford model
Rutherford model of atom is the model which explains that there is a nucleus in the center of the atom and electrons are located around the nucleus.
3. Relative atomic mass. Atoms have very little mass , so they're difficult to measure accurately. Instead, chemists use a scale. On this scale the mass of a 12C atom is exactly 12.
4. Difference between Alpha, Beta and Gamma radioactive decay:
Alpha decay forms new element with two fewer protons and two fewer neutrons;
Beta decay forms new element with one more proton and one fewer neutron.
Gamma decay forms NO new element, but now the element has less energy because energy is released as gamma rays.
Gamma radiation has the highest penetration power, Beta decay goes the second, alpha decay the last. However, alpha particles make the most damage even if it has the lowest penetration power among the three.
5. This species has a 2− charge on it, so it is an anion. Anions are named using the stem of the element name with the suffix -ide added. This is the oxide anion.
Hope it helps....Pls Mark as Brainliest!! I Have answered all your question in the Simplest way i could...
The crackling sound Is mainly to do with chemistry, The fireworks are filled with lead oxide, which turns into lead atoms as the firework explodes and heat up—— whistling sounds, the whistle is down to the tube being narrow one, thus rockets make a whistling noise
The pH value can be measured using electrochemical measuring systems, litmus paper, or indicators and colorimeters. The easiest way to take a pH measurement is to use litmus paper or a colorimeter. The advantage of this type of pH measurement is that the pH range is well known and they are easy to apply.
