Which is the least reliable indicator of a chemical change?

change of color

change of odor

formation of gases

change of shape

1: a chemical change

2: the components of the pure substance will not be able to be separated by physical means

3: true

4: false

5:change of shape

6:a chemical change

7: false

8:false

9:solid

10: It reacts with hydrogen to form a gas.

11:false

12: false

answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck

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.