Tutor profile: Elliott C.
What is a common greeting used in France ?
While the formal greeting would be "Bonjour", a more common one is " Salut! ".
What are Isotopes? Are they dangerous?
Isotopes are two atoms with the same atomic numbers ( position in the periodic table, or number of protons ), but vary by their numbers of neutrons contained in their nuclei. While most known Isotopes do not emmit harmful radiations, some Isotopes do (specifically gamma ray).
Subject: Materials Science
Shower curtains and pipes are both made of PVC, how can the same material have such different mechanical properties ?
While PVC pipes and shower curtaisn have the same material base, different additives are added throughout the manufacturing process to allow for different mechanical properties. For shower curtains, chemicals known as plasticizers are added. These molecules will interact with the polymer chains and allow them to move more freely with regard to each other, allowing the material to be more flexible. For PVC pipes, no plasticizers are added, but innorganic fillers such as carbon black or chalk can be added to prevent UV decay or impact the final product's color.
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