Answer: The correct option is b.
Explanation: Chemical reaction is a reaction i which the chemical composition of the reactants gets changed and new substances having different chemical composition is formed. This reaction cannot be reversed by any physical means.
Indicators showing chemical changes are :
- Color change
- Characteristic odor
- Formation of bubbles
- Formation of precipitate
From the given information above, it can be stated that the correct option is b.
Answer:
An emerald can be described as a pure substance because it is a compound. it's a pure substance because it is an element. It's an impure substance because it is chemically combined, an impure substance because it is a mixture.
Explanation:
4 moles of sodium because you originally have 2.0 moles of Na2SO4 and you set that up at the beginning of the (what we called) train tracks. Then diagonally from that, on the bottom you put 1 mol of Na2SO4 to cancel the units. Then above that you have 2 moles of sodium because that is how many there are in the equation that they gave (the Na2 part). Then its just like a fraction, you multiply the top by the top and the bottom by the bottom, which would give you 4moles/1 or just 4 moles Na. I hope that helps
False..........
it has so many consequences
