Stu and noke are working with a red food coloring, red #40. the stock solution has a concentration of 0.0880 m dye. noke want to makes a concentration of 0.0088 m, exactly one tenth of the original red dye solution strength. what volume of the original 0.0880 m solution should she measure into a 100.0 volumetric flask, to be diluted with water up to the line of the flask? (3 significant digits, unit ml)

2)stu dilutes the stock 0.0880 m red dye solution (same as the previous question by measuring 25.00 ml with a pipet into a 100.0 ml volumetric flask and then adding water up to the line on the flask. calculate the new concentration of his diluted solution. (round to 3 significant digits, unit m)

1. Volume of the original 0.0880 M solution should Nok measure into 100 mL volumetric flask is 10.0 mL.

2. The new concentration of diluted solution is 0.0352 M.

Explanation:

1) Concentration of solution given =

Volume of solution red dye solution of 0.0880 M needed =

Required concentration of red dye solution =

Volume of solution red dye solution required=

Volume of the original 0.0880 M solution should Nok measure into 100 mL volumetric flask is 10.0 mL.

2) Concentration of red dye solution given =

Volume of solution red dye solution of 0.0880 M added into volumetric flask=

Required concentration of red dye solution =

Volume of solution red dye solution required=

The new concentration of diluted solution is 0.0352 M.

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"