Insulin is a protein that is used by the body to regulate both carbohydrate and fat metabolism. A bottle contains 225 mL of insulin at a concentration of 20.0 mg/mL . What is the total mass of insulin in the bottle?

The total mass of insulin in the bottle : m = 4500 mg

Given

225 ml of insulin

The concentration 20 mg/ml

Required

The total mass of insulin

Solution

Density is the ratio of mass per unit volume

Can be formulated

ρ = m / V

m = ρ x V

Input the value :

m = 20 mg/ml x 225 ml

m = 4500 mg

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.