Answer:
Follow safety measures and safety rules to avoid any accident.
Explanation:
1. Follow all safety measures is needed from adults when they conducting any experiment at home in order to prevent any damage occurs due to that experiment.
2. Safety rules should always be followed when conducting an experiment at any place such as at home, class room and laboratory etc in order to avoid any accident.
3. Some chemicals are very dangerous because they are flammable and catch fire when allow it to the heat source. Some chemicals also cause suffocation by absorbing all the oxygen from the environment and as a result death occurs.
4. Science is a systematic study of physical objects through observation and experiments. Science is a knowledge gain from experiments.
Suppose X (in unit M) be the required maximum concentration of the Pb(NO₃)₂ solution added after mixing with 100 ml of 6.5 x 10⁻² M NaCl, the Pb²⁺ concentration is:
[Pb²⁺] = (X*100) / 200 = 0.5 X
The concentration of Cl⁻ is:
[Cl⁻] = (100 / 200) * (6.5 x 10⁻² M) = 0.0325 M
So:
Ksp = 2.00 x 10⁻⁵ = [Pb²⁺] [Cl⁻]² = (0.5X) * (0.0325)²
X = (2.00 x 10⁻⁵) / (5.28 x 10⁻⁴) = 0.038 M
A): The closest orbital to the nucleus, called the 1s orbital, can hold up to two electrons. This orbital is equivalent to the innermost electron shell of the Bohr model of the atom. It is called the 1s orbital because it is spherical around the nucleus. The 1s orbital is always filled before any other orbital.
