Suppose you have 2.50 L of a substance with a density of 8.00 g/mL and you want to determine the mass of the substance. The calculation can be broken down into three steps. First, convert the volume from liters to milliliters. Then, determine the mass of the sample in grams. Finally, convert the mass from grams to kilograms. Show the unit analysis by placing the correct components into the unit‑factor slots. The question marks (?) represent the answer to the previous step.

20 kg

Explanation:

From the question given above, the following data were obtained:

Volume (V) of substance = 2.50 L

Density (D) of substance = 8.00 g/mL

Mass (m) of substance =?

Next, we shall convert 2.50 L to millilitres (mL). This can be obtained as follow:

1 L = 1000 mL

Therefore,

2.50 L = 2.50 L × 1000 mL / 1 L

2.50 L = 2500 mL

Thus, 2.50 L is equivalent to 2500 mL.

Next, we shall determine the mass of the substance. This can be obtained as follow:

Volume (V) of substance = 2500 mL

Density (D) of substance = 8.00 g/mL

Mass (m) of substance =?

D = m / V

8 = m / 2500

Cross multiply

m = 8 × 2500

m = 20000 g

The mass of the substance is 20000 g.

Finally, we shall convert 20000 g to Kg

This can be obtained as follow:

1000 g = 1 kg

Therefore,

20000 g = 20000 g × 1 kg / 1000 g

20000 g = 20 kg

Therefore, the mass of the substance is 20 Kg

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.