Answer:
the teacher means that if she had done more research she wouldve had a better result
Explanation:
Answer : The correct answer for molarity of MgCl₂ solution is 0.67 M.
Molarity :
It expresses concentration of any solution . It can be defined as mole of solute present in volume of solution in Liter .
It uses unit M or 
It can be formulated as :

Given : mol of MgCl₂ (solute ) = 0.50 mol
Volume of solution = 750 mL
Following steps can be done :
Step 1 ) To convert volume of solution from mL to L
1 L = 1000 mL

Volume of solution = 0.750 L
Step 2) To find molarity
Plugging mole of solute and volume of solution in molarity formula as :


Hence molarity of MgCl₂ solution is 0.67 M
Zn (s) -> Zn+2 (aq) + 2e-
Zn (s) with a neutral charge is oxidized and looses two electrons in the process to form ZnCl2 (aq) where Zn has a charge of 2+.
Answer:
2. 100 times more hydroxide ions,
Explanation:
Acidity and alkalinity are measured with a logarithmic scale called pH. Each one-unit change in the pH scale corresponds to a ten-fold change in hydrogen ion concentration. Therefore, a 1.0 liter aqueous solution with a pH of 5.0 contains 100 times more hydronium ions than a 1.0 liter aqueous solution with a pH of 7.0