Question

Question:1

Calculate the density, in g/cm³, of a metal that has a volume of 41.3 L and a mass of 70.05 kg.

Question:2

You have 20.0 L of a 8.18% by volume (% v/v), water-based dye solution. Calculate the volume of pure dye and water that were used to prepare the solution. You may assume that volumes are additive.

Question:3

How many mL of pure (100.0%) food dye are needed to prepare 437.4 mL of 34.8% by volume (%v/v) food dye solution? You may assume that volumes are additive.

Answer 1

Question:1

determine the color of light associated with electromagnetic radiation having the following wavelengths:

Solution : -

470 nm = Blue

545 nm = Green

595 nm = Yellow

705 nm = Red

Question:2

Calculate the density, in g/cm³, of a metal that has a volume of 41.3 L and a mass of 70.05 kg.

Solution :-

Converting kg to gram

And L to cm3

70.05 kg * 1000 g/ 1 kg = 70050 g

41.3 L * 1000 cm3 / 1 L = 41300 cm3

Density = mass / volume

              = 70050 g / 41300 cm3

           = 1.696 g/cm3

Therefore density = 1.696 g/cm3

Question:3

You have 20.0 L of a 8.18% by volume (% v/v), water-based dye solution. Calculate the volume of pure dye and water that were used to prepare the solution. You may assume that volumes are additive.

Solution :- volume of solution = 20.0 L

% 8.18 % v/v dye

Therefore volume of the dye = 20.0 L * 8.18 % / 100 % = 1.636 L

Volume of water = volume of solution – volume of dye

                            = 20.0 L – 1.636 L

                           = 18.364 L

Therefore volume of dye = 1.636 L and volume of water = 18.364 L

Question:4

How many mL of pure (100.0%) food dye are needed to prepare 437.4 mL of 34.8% by volume (%v/v) food dye solution? You may assume that volumes are additive

Solution :-

Volume of solution = 437.4 ml

% dye = 34.8 % v/v

Therefore the volume of the dye needed is calculated as

437.4 ml * 34.8 % / 100 % = 152.2 ml dye

So we need 152.2 ml of 100 % pure dye and then dilute it to 437.4 ml by adding water.