Select all that apply to colloids.
a.) a colloid is a mixture intermediate between heterogeneous and homogenous. b.) colloids cannot be separated by filtration.
c.) colloids can be seen using an optical microscope.
d.) fog and smoke are examples of colloids.
e.) the tyndall effect is a test to determine whether or not a mixture is a colloid.

what is the volume occupied by 40 grams of argon gas (ar) at standard conditions? what volume, in liters, is occupied by 1.5 x 1023 

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.