How many atoms of carbon are present in 200 mg of Ibuprofen.

7.5 x 10²¹atoms

Explanation:

Chemical formula of the compound:

       C₁₃H₁₈O₂

Given mass  = 200mg

Unknown:

Number of atoms in 200mg ibuprofen = ?

Solution:

We need to find the number of moles represented by this mass;

   Number of moles  =

Molar mass of  C₁₃H₁₈O₂ = (12x13) + (1 x 18) + (16 x 2) = 206g/mol

 Input the parameter and solve for the number of moles;

    Number of moles = = 0.00097mol

          In  1 mole of C₁₃H₁₈O₂ there are 13 mole of carbon;

'         So, in 0.00097mol, we will have 13 x 0.00097mol  = 0.013mole

  1 mole of an atom contains 6.02 x 10²³ atoms

  0.013 mole of Carbon will contain 0.013 x  6.02 x 10²³ atoms

                                               = 7.5 x 10²¹atoms

b) mutualism

hope this : )

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

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e