Characteristics of acid
-It tastes sour
-It reacts with metals and carbonates
-It turns blue litmus paper red
Characteristics of base
-It tastes bitter
-It feels slippery
-It turns red litmus paper blue.
4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
It's called a compound because different elements are held together by a chemical bond.
I believe it is C, but I can't guarantee it.
