How many grams of a solution that is 5.2% sucrose by mass are needed to obtain 18g of sucrose

346.g of solution

Explanation:

In this case, if we have 5.2 % by mass it means that in 100 g of the solution we will have 5.2 g of glucose. Therefore we can do the calculation:

5.2 g of glucose = 100 g of solution

So, if we need 8 g of glucose we had to have 346.15 g of solution

This logic can work for all types of solutions. By mass (as in this case), by volume or mass/volume.

I hope it helps!

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.