Concentrations 1) calculate the mass of sucrose and the mass of water (in grams) that must be used to prepare 400 g of 50% by mass of sucrose solution. since a solvent is present in greater proportion than the solute in a solution, do these terms still apply at 50% by mass concentration? why?

2) if a wine sample is 12.0% by volume ethanol, how many milliliters of ethanol is present in a bottle containing 500.0 mL of the wine? if other alcoholic drinks have relatively high concentration 35 to 50% (v/v) ethanol, is wine safer to drink before driving? why?

3) a pancake recipe recommends a 65% (v/v) sugar syrup concentration. if you wish to prepare the recipe and you only have 50 g of sugar at home, how will you prepare the syrup? if based on the recipe, one pancake will need 5 mL of the syrup, how many pancakes should you make to use all the syrup you made?

pls help >.