Several centimeters of lead. Gamma rays have the highest penetrating power and therefore need a thick layer of something, in most cases lead, to prevent penetration. (This is why if you have ever go to the dentist they put a heavy thing on you made of lead, to prevent the penetration of gamma rays that can destroy your most important organs).
Answer: Alkali metals, halogens, noble gases
Explanation:
Ionic compounds are made of ions- charges. In LiF and NaCl, the first element has a +1 and the second element has a charge of -1. Elements that are +1 are alkali metals and elements that are -1 are halogens. Noble gases have full octets in their outermost valence shell, and since they're full it's so stable so it doesn't react with anything.
The number of protons and neutrons in the nucleus : 92 and 146
<h3>Further explanation</h3>
Given
Mass number = 238
Atomic number = 92
Required
Protons and neutrons
Solution
Mass number=number of protons + neutrons
Atomic number=number of protons=number of electrons
Atomic number = 92⇒number of protons=92
Number of neutrons = mass number - atomic number
Number of neutrons = 238 - 92 = 146
Answer: Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.
Explanation:
Answer:
Quartenary.
Explanation:
Quaternary ammonium compounds (QACs) are cationic salts of organically substituted ammonium compounds and have a broad range of activity against microorganisms, i.e more effective against Gram-positive bacterium at lower concentrations than Gram-negative bacteria.
It was also reported previously that monoalkyl QACs bind by ionic and hydrophobic interactions to microbial membrane surfaces, with the cationic head group facing outwards and the hydrophobic tails inserted into the lipid bilayer, causing the rearrangement of the membrane and the subsequent leakage of intracellular constituents.
